(navigation image)
Home American Libraries | Canadian Libraries | Universal Library | Community Texts | Project Gutenberg | Children's Library | Biodiversity Heritage Library | Additional Collections
Search: Advanced Search
Anonymous User (login or join us)
Upload
See other formats

Full text of "Bulletin of the British Museum (Natural History) Geology Supplement"



i^. 



«=■ 



L 



JURASSIC BIVALVIA AND 
GASTROPODA FROM TANGANYIKA 

AND KENYA 



L. R. COX 



BULLETIN OF 
THE BRITISH MUSEUM (NATURAL HISTORY) 
GEOLOGY Supplement i 

LONDON : 1965 



JURASSIC BIVALVIA AND GASTROPODA 
FROM TANGANYIKA AND KENYA 




BY 
LESLIE REGINALD COX, M.A., Sc.D., F.R.S. 



\ 



30 Plates ; 2 Text-figures 



BULLETIN OF 

THE BRITISH MUSEUM (NATURAL HISTORY) 

GEOLOGY Supplement 1 

LONDON : 1965 



THE BULLETIN OF THE BRITISH MUSEUM 

(natural history), instituted in 1949, is issued 
in five series corresponding to the Departments of 
the Museum, and an Historical series. 

Parts will appear at irregular intervals as they become 
ready. Volumes will contain about three or four 
hundred pages, and will not necessarily be completed 
within one calendar year. 

In 1965 a separate Supplementary series of longer 
papers was instituted, numbered serially for each 
Department. 

This paper is Supplement No. 1 of the Geological 
{Palaeontological) series. The abbreviated titles of 
periodicals cited follow those of the World List of 
Scientific Periodicals. 



Trustees of the British Museum (Natural History) 1965 



TRUSTEES OF THE 
BRITISH MUSEUM (NATURAL HISTORY) 

Issued October, 1965 Price: £6 



JURASSIC BIVALVIA AND GASTROPODA 
FROM TANGANYIKA AND KENYA 



By L. R. COX 



CONTENTS 

I Introduction .......... 

II History of investigation of Jurassic Mollusca of East Africa 

III East African Jurassic bivalve and gastropod faunas and 

their characteristics ........ 

IV Systematic descriptions. ....... 

V List of fossil localities, with species collected from each . 

VI References .......... 

SYNOPSIS 



Page 
4 
5 

10 

25 

J 74 

198 



Jurassic Bivalvia and Gastropoda from Tanganyika and Kenya in the collections of the 
British Museum (Natural History) are described in this memoir. The bulk of the material has 
come from three sources, the British Museum East Africa Expeditions (1924-31), the Geological 
Survey Departments of the two territories concerned, and the B.P.-Shell Petroleum Development 
Company of Tanganyika, Ltd. 207 species of Bivalvia and 56 of Gastropoda are described, but 
among them are 10 identified only generically and 12 of which the specific identifications have 
been qualified or queried. The totals include 84 new species of Bivalvia and 33 of Gastropoda, 
while one bivalve species has been re-named on account of homonymy. One new subgenus of 
Bivalvia, Africomiodon (subgenus of Eomiodon), and one new genus of Gastropoda, Africoconnlns, 
are erected. 

The strata which have yielded the specimens described range from Toarcian to uppermost 
Jurassic in age. The occurrence of many species found also in the European Jurassic confirms 
evidence from other parts of the world of the very wide geographical distribution of such forms. 
These widespread species are particularly abundant in the Callovian and Oxfordian material. 
At the same time, the existence of a subprovince which included countries surrounding the 
western part of the Indian Ocean (Madagascar, Arabia, India and Pakistan, as well as East 
Africa) is indicated by the occurrence of a number of well-characterized species found in one or 
more of the other countries mentioned, but not in Europe. Ignoring the qualifications (" cf." 
and " aff.") of a few identifications, these results are summarized in the following table: 









Species 




Species 




Species 


New 


known 


Species 


found in 


Geological Stage 


here 


species 


only from 


found in 


India etc. 




recorded 




E. Africa 


Europe 


but not 
Europe 


Kimmeridgian 


92 


35 


56 


32 


3 


Oxfordian . 


53 


16 


21 


27 


5 


Callovian 


46 


5 


8 


32 


6 


Bathonian* 


10 


4 


4 


4 


2 


Bajocianf . 


44 


29 


27 


12 


4 


Toarcian 


30 


22 


22 


7 


1 


*Including Asaharbito Beds. 












tincluding Pindiro Shales. 













4 JURASSIC BIVALVIA AND GASTROPODA 

1 INTRODUCTION 

During the past 40 years numerous fossil invertebrates from the Jurassic rocks of 
East Africa have been added to the collections of the British Museum (Natural 
History). This material has come from several sources. From 1924 to early in 
1931 the Museum sent a series of expeditions to collect from the dinosaur beds of 
Tendaguru, Tanganyika, under the leadership of W. E. Cutler, J. Parkinson and 
F. W. H. Migeod in succession, and the material brought back to England included 
many invertebrate specimens as well as dinosaur bones. From about the same 
period to the present day the Geological Survey Departments of Tanganyika and 
Kenya have from time to time sent collections of fossils to London for identification, 
and the material from these sources which has been deposited in the Museum during 
the past few years has been particularly extensive. From 1951 to 1959 the B.P.- 
Shell Petroleum Development Company of Tanganyika Ltd. investigated a con- 
siderable area of the coastal region of the two territories and a selection from the 
Jurassic specimens collected has been generously presented to the Museum. Small 
collections from East Africa have also been acquired by the Museum from other 
sources. Preliminary reports on some of the Geological Survey material have 
appeared in the publications of these institutions, and in a few cases these have 
included illustrations of some of the fossils. Otherwise, the only publications 
dealing with Jurassic bivalves and gastropods from this region now in the Museum 
consist of two short notes by the present writer (Cox, 1937a, 1937&). It has, there- 
fore, now seemed appropriate to describe in a single memoir all the East African 
Jurassic material belonging to these classes which is now available in London. 

This account has been written at a time when there are movements afoot to 
stabilize Jurassic stratigraphical nomenclature by international agreement. It 
seems probable that the decision may be reached to restrict the range of the Kim- 
meridgian stage in accordance with non-British usage, and possible that the term 
Portlandian may be abandoned. It is, however, uncertain what stage name (Vol- 
gian or Tithonian) will be accepted for Jurassic beds of later date than the restricted 
Kimmeridgian. In East Africa ammonite evidence establishes the age of the pre- 
Cretaceous marine beds at Tendaguru as Upper Kimmeridgian in the British sense 
(Arkell 1956 : 355), and there is no palaeontological evidence for correlating any 
deposits with the type Portlandian or with post-Kimmeridgian (sensu anglico) 
horizons of the European Tithonian. It has therefore been decided to use the term 
Kimmeridgian in the British sense in the present memoir, to dispense with the 
terms Portlandian and Tithonian, and merely to allude to very late Jurassic beds, 
the exact age of which is unestablished, as " uppermost Jurassic ". 

The writer expresses his great indebtedness to all who have placed specimens and 
information at his disposal, particularly successive Directors and members of the 
staffs of the Tanganyika and Kenya Geological Surveys, and Dr. F. E. Eames and 
his colleagues of the palaeontological staff of the British Petroleum Company, Ltd. 
Mr. D. L. F. Sealy, of the Department of Palaeontology of the British Museum 
(Natural History), has drawn the two sketch-maps appearing as text-figures, and 



FROM TANGANYIKA AND KENYA 5 

Mr. C. P. Palmer, of the same Department, has rendered invaluable assistance with 
the preparation of many of the fossil illustrations. 

II HISTORY OF INVESTIGATION OF JURASSIC MOLLUSCA OF EAST AFRICA 

Knowledge of the Jurassic stratigraphy and palaeontology of East Africa has 
been reviewed at rather frequent intervals as it has progressed during the past 
hundred years. Successive works which may be particularly mentioned in this 
connection are those of Neumayr (1885), Dacque & Krenkel (1909), Behrend (1918), 
Krenkel (1925), Arkell (1956), Aitken {in Quennell et at., 1956 ; also in Quennell 
et al., 1957), and Pulfrey (1963). In view of the existence of these works, particularly 
the later ones, it is necessary for the purposes of the present memoir to do little 
more than summarize the history of the study of the Jurassic bivalves and gastro- 
pods of the region, although a few passing references may be made to work on the 
ammonites. 

The earliest record of the occurrence of marine Jurassic rocks in East Africa was a 
short note by Fraas (1859) recording the discovery by a missionary, J. L. Krapf, of 
an ammonite at Kisaludini, near Mombasa. This specimen, originally identified 
as Ammonites annularis Reinecke, was subsequently described as Perisphinctes 
(Virgatosphinctes) krapfi by Dacque (1910 : 13, pi. 3, fig. 3), who showed that its age 
was Upper Oxfordian and not Upper Dogger (Callovian), as supposed by Fraas. 

Beyrich (1877, 1878) published two short papers on ammonites which the ex- 
plorer J. M. Hildebrandt had sent to him from localities near Mombasa, his con- 
clusion being that various stages of the Jurassic are represented in the district. In 
the account of his journey Hildebrandt (1879 : 2 54> 2 7 2 ) mentioned the occurrences 
of Jurassic beds in the district. Further south, in Usambara, the northern coastal 
district of Tanganyika, fossiliferous rocks now known to belong to the Jurassic were 
recorded by the English traveller J. Thomson (1879, 1881), but he thought that their 
fossils suggested a Carboniferous age. Farler (1879 : 87) referred to the occurrence 
of a fossiliferous pisolitic limestone in the same area but made no suggestion regard- 
ing its age. 

Baumann (1891 : 4, 116), in his work on Usambara, definitely recorded the pre- 
sence of Jurassic rocks in that area but cited none of the included fossils by name, 
and in the same year Stuhlmann (1891) referred to the outcrop of a narrow belt of 
Jurassic rocks behind the Tertiary formations near Pangani, further south, mention- 
ing that they contained ammonites. A number of fossils, mostly ammonites, 
collected by Stuhlmann at the locality Mtaru were described by Tornquist (1893), 
who assigned an Oxfordian age to them ; no bivalves or gastropods were mentioned. 
In the same year, Jaekel (1893) published a short note on some Jurassic fossils from 
Usambara sent to Germany by G. Lieder, by then established as official geologist in 
what was at that time German East Africa. For the first time reference was made 
to some Bivalvia, including an oyster said to be scarcely separable from Ostrea 
dextrorsum Quenstedt (a probable synonym of Lopha solitaria (J. de C. Sowerby)), 
a Lima and a PseudomonotisH , neither identified specifically. An Upper Jurassic 
age was assigned to these forms. In the next year Stuhlmann himself (1894a, b) 



o J I RASSIC BIVALVIA AND (.ASTROPODA 

published two short papers in which he referred to the presence of Jurassic rocks 
in the hinterland of Dar es Salaam and Bagamoyo, mentioning the occurrence of 
fossil molluscs in them without citing any specific names. 

Futterer (1894) reviewed occurrences of Jurassic rocks in the hinterland of Mom- 
basa, Tanga, Saadani and Dar es Salaam in the light of fossils sent to Germany by 
Hildebrandt, Lieder and von dem Borne. Although mainly devoted to ammonites, 
thought to belong to stages ranging from Callovian to Kimmeridgian or possibly 
Tithonian, this paper may be noted particularly as containing the description of the 
first supposedly new bivalve species from the East African Jurassic. It was a 
Chlamys described (Futterer 1894 : 91, pi. 5, figs. 4, 4a) as Pecten bipartitus and 
came from beds at Mkusi 1 , near Tanga, thought to be Oxfordian in age. In the 
present work it is suggested that the form in question should be regarded as a syno- 
nym of the European species Chlamys snbtextoria (Munster). 

The most important contribution to the Mesozoic palaeontology of East Africa 
that had so far appeared was Midler's (1900) description of the fossils collected by 
W. Bornhardt. This material came from 23 localities in Tanganyika. The beds at 
nine of these were assigned to various stages of the Jurassic and those at 14 to the 
Cretaceous, but it has since been suggested that two of the 14 belonged to the upper- 
most Jurassic and a third to an earlier stage of that system. Most of the Jurassic 
localities were situated in the hinterland of Kiswere, in the southern part of the 
territory, but one lay to the north-west of Kilwa and others in the hinterland of 
Dar es Salaam and Bagamoyo. The Jurassic bivalves and gastropods described by 
Miiller included a number of forms definitely or tentatively referred to species pre- 
viously known from Europe, but the following were regarded as new: Cucullaea 
lasti, Isocardia subtenera, Ceromya acquatorialis , Avicula lieberti, Area uitenhagensis , 
Trigonia beyschlagi, Protocardia schencki, Exogyra solea, Straparollus suprajurensis, 
Nerinea credneri. In the present memoir some of these are regarded as synonyms 
of species which had been described previously, and one or two are recorded from 
further localities ; five, however, have not been encountered in the material studied. 

A note published by Menzel (1902) dealt with Jurassic fossils collected by Dantz 
in Tanganyika. These included a number of bivalves, some of which were referred 
to species already known from Europe ; two, however, to which the new names 
Pecten muelleri and Gervillia dantzi were assigned, but which are not identifiable from 
the brief descriptions, were recorded from beds thought to be Bathonian in age at a 
locality near Kibwendere on the Ngerengere river. Koert (1904) recorded the 
presence of Callovian beds, identified by their ammonites, near Tanga, but did not 
list any other mollusca. Fraas (1908a) gave an account of his observations on the 
dinosaur beds at Tendaguru and neighbouring localities in the Lindi hinterland, 
mentioning the abundance of a trigoniid which he recorded as Trigonia beyschlagi 
Miiller, and referring also to a limestone full of nerineids. He considered all the 
beds to be Cretaceous in age. The same author (19086) also published a short 
account of observations on Jurassic rocks exposed along the railway lines running 
inland from Dar es Salaam and from Mombasa respectively. Among the sections 

\itkcn, in Quennell el al., 1956 : 157. 



FROM TANGANYIKA AND KENYA 7 

of beds illustrated was one near Pendambili (now Magindu) station 2 , from which an 
engineer, Kinkelin, had forwarded a series of fossils to Germany. E. Dacque's 
determinations of the fossils from this locality, which included a few bivalves, were 
cited in the paper. 

In 1910 Dacque published a memoir on the Jurassic fossils from Mombasa and 
from the Pendambili quarry which Fraas, Kinkelin, and others had collected. The 
Mombasa material consisted only of cephalopods of Upper Jurassic age. The 
Pendambili fossils, which were evidently Callovian in age, included a number of 
bivalves, some of which were referred to species already known from Europe. 
Among them, however, was a new astartid, Astarte muelleri, considered to be identical 
with a form from southern Tanganyika which Miiller (1900 : 534, pi. 17, fig. 7) had 
figured under the name Astarte sp. In the same year Krenkel (1910) published an 
account of invertebrate fossils collected by Fraas from the neighbourhood of Tenda- 
guru. These were still all considered to be Cretaceous in age, but included some 
forms now known to have come from Upper Jurassic beds. Among the last were the 
supposedly new species Avicula tschingira, Pinna "g. niiilleri" , Perna tendagura, and 
Trigonia matapuana, the last founded on what was probably a young specimen of 
the " Trigonia smeei " group. 

The scientific results of the German expeditions (1909-12) to collect from the 
dinosaur beds of Tendaguru were published in 1914. Dietrich, in his account of the 
gastropods, described the following new species of Upper Jurassic age : Rhytidopi- 
lus obliquus, Physa tendagurensis, Patella kindopensis, Nerita (Lissochilus) stremmei, 
Pseudomelania (Oonia) recki, and Nerinea hennigi. He also recorded the common 
Tendaguru nerineid under the name Nerinella credneri (Miiller), the original type- 
specimens of which had come from beds of Callovian age. At the same time Hennig 
(19146) described the bivalves of the saurian beds, apart from the trigoniids, which 
were dealt with in a separate paper by Lange (1914). Hennig recorded a number of 
species already known from the Jurassic of Europe, but described three supposedly 
new forms, Citcullaea irritans, Gryphaea bubo, and Pseudomonotis tendagurensis. 
Lange referred the common trigoniid from the Tendaguru series to the species 
Trigonia smeei J. de C. Sowerby, originally described from India, placing T. beyschlagi 
Miiller in its synonymy, and a second Jurassic species was described by him under 
the new name T. dietrichi. 

In a subsequent paper Hennig (1917) referred to a small series of molluscs which 
he had obtained from black calcareous concretions occurring in a shale formation 
(the Pindiro Shales) along the Pindiro valley, north-west of Lindi, in southern 
Tanganyika. The specimens collected, which were not figured, were recorded as 
Gervillia aff. iraonensis Newton, Cypricardia aff. nuculiformis (Roemer), Neaera sp., 
"Alaria, Gruppe der Al. hamus" , and " ? Cryptaulax, Gruppe der armata Goldf. sp." 
The age of this assemblage was thought to be most probably " Upper Dogger ". It 
is probable that most of the forms recorded belonged to species found in the shales 
themselves and described under other names in the present memoir. 

2 See Aitken, in Quennell et al., 1956 : 178, footnote, for information about the position of the Pen- 
dambili quarry, which was about 2 km. east of Magindu station. 



8 JURASSIC BIVALVIA AND GASTROPODA 

In the same year Lange (1917) reverted to the subject of the Tendaguru trigoniid 
which he had recorded as Trigonia smeei J. de C. Sowerby in 1914. He remarked 
that this species appeared to be a characteristic fossil of the Tithonian, and also 
noted that there was some similarity between it and a South American form which 
Jaworski had described as Trigonia burckhardti. 

Reck (1921) described a small series of molluscs collected along the railway running 
inland from Dar es Salaam. The specimens came from a section between 139-5 and 
I 39'75 km. from that town (according to the former alignment of the railway, since 
changed), that is, a little to the west of Kidugallo station. In addition to several 
forms identified only generically, the species recorded included a representative of 
a new genus of Arcticidae (Dietrichia parvula gen. et sp. nov.) and a small gastropod 
described as Neritodomus subkidugallensis sp. nov. The fossil evidence was not 
clear enough to enable an exact date to be assigned to this bed, but Reck considered 
that not only was it the lowest fossiliferous horizon exposed locally, but also that it 
was the lowest horizon with marine Jurassic fossils which up to then had been found 
anywhere in East Africa. He considered that it might lie close to the boundary of 
the Upper Lias and Dogger. In 1924 Hennig published a detailed account of the 
Jurassic beds, ranging from the Lower Dogger to the Lower Malm in German termino- 
logy, exposed along and near the same railway, between Kidugallo and Ngerengere. 
He recorded and in some cases figured a number of bivalve and gastropod species 
previously known from Europe or elsewhere, and described the following as new : 
Modiola menzeli [Upper Dogger ; not figured], Ostrea {Alectryonia) bornhardti 
[Upper Dogger], Isocardia substriata [Callovian], Pteroperna africana [" Lower 
Malm "], Corbula pseudomucronata [Oxfordian], Anisocardia recki [Oxfordian]. 

Dietrich (1925) gave an account of fossils collected in the Mandawa-Mahokondo 
area of Tanganyika, where the succession of Upper Jurassic beds is entirely marine 
and uninterrupted by dinosaur-bearing beds as at Tendaguru. His paper dealt 
mainly with the cephalopods, but the small number of bivalves recorded included a 
new species, Gryphaea hennigi, thought to be Kimmeridgian in age. Gregory (1927) 
placed on record the discovery near Mombasa of a specimen of the species then 
known as Parallelodon egertonianus (Stoliczka), already discovered in Somaliland 
and Arabia as well as in the Himalayas, where it occurs typically in the Spiti Shales. 
Two years later a note by Parsons (1929) recorded the presence of the bivalve 
Posidonia cf. ornati Quenstedt in the Miritini Shales (Callovian) of the Mombasa 
district. 

This period was marked by a renewal, on the part of Kitchin (1926, 1929), of the 
discussion initiated by German workers regarding the age of the dinosaur beds at 
Tendaguru. Kitchin (1929 : 208), as the result of his work on the Cutch Jurassic 
bivalves, had concluded erroneously that Trigonia smeei occurs in that area in Lower 
Cretaceous beds, and was therefore loath to accept the conclusion that the " T. 
smeei " beds at Tendaguru belonged to the Upper Jurassic, particularly as certain 
species (Trigonia ventricosa (Krauss), Seebachia bronni (Krauss), Astarte herzogi 
(Goldfuss) and Gervillia dentata (Krauss)) originally described from the Lower Cre- 
taceous Uitenhage beds of South Africa had been recorded from them. Ammonites 



FROM TANGANYIKA AND KENYA g 

which Spath had pronounced to belong to the Middle Kimmeridgian had, it is true, 
also been found at Tendaguru, but Kitchin suggested that these were derived speci- 
mens and maintained that all the beds exposed there belonged to the Lower Cre- 
taceous. This contention evoked rejoinders from Dietrich (1927) and Hennig (1927). 
It was, however, not long before Spath showed that in India T. smeei occurs in 
Oxfordian and not in Lower Cretaceous beds, and the dispute about the beds at 
Tendaguru was not continued. Actually, the records of Uitenhage species from the 
" T. smeei " beds appear to have been unreliable. 

In the third of a series of monographs, inspired by J. W. Gregory, on collections 
of fossils from N.E. and E. Africa which had been presented to the Hunterian 
Museum, Glasgow University, Weir (1930) described a series of molluscs and brachio- 
pods from the Mombasa district, largely collected by Miss M. McKinnon Wood. 
The formations from which the material described was collected ranged from the 
Kambe Limestone (Upper Bajocian-Bathonian) to the Changamwe Shale (Upper 
Oxfordian-Kimmeridgian). Bivalves described included a number of forms assigned 
either definitely or with qualification to European species and no new species were 
described. 

An important monograph by Dietrich (1933) supplemented the earlier works deal- 
ing with ammonites and bivalves collected by the German expeditions to Tendaguru. 
91 bivalves (53 from the Upper Jurassic and 38 from the Cretaceous) were recorded 
in this work, the Jurassic forms including the following new species or varieties : 
Lithophaga suboblonga, Oxytoma ineqnivalvis var. hennigi, Stegoconcha solida var. 
tendagurensis [previously described by Krenkel as Pinna g. miilleri], Pecten (Chlamys) 
curvivarians, Alectryonia hennigi, Epihippopodium quenstedti, Astarte recki, Astarte 
subobovata, Astarte krenkeli, Astarte weissermeli, Seebachia janenschi , Corbis (Spliaera) 
subcorrugata, Cardium (Tendagnrium) propebanneianum, Arcomya (Pachymya?) 
robustissima. 

A memoir by Hennig (1937) on the sedimentary formations of the Lindi-Kilwa 
hinterland included a palaeontological section in which, in addition to a number of 
previously known forms, the following new gastropod and bivalve species were 
described : Nummocalcar (Platybasis) dietrichi [Kimmeridgian, Tunduru], Clavotri- 
gonia discordans [" Trigonia smeei " bed, Tunduru], Lima matumbiana [Dogger, 
Matumbi]. In the same year the present writer (Cox 1937a, b) published two papers 
in which a few bivalves collected by G. M. Stockley, of the Tanganyika Geological 
Survey, were described. A new subgenus, Indogrammatodon, was founded for the 
reception of the Indian Jurassic species Cucullaea virgata J. de C. Sowerby and rela- 
ted forms, and a new species, Grammatodon {Indogrammatodon) stockleyi, was 
described from beds of Callovian age about n miles S.E. of Lugoba, Tanganyika. 
A new trigoniid species, Trigonia tealei, was based on specimens from the same 
locality, and was also recorded, with several other species, from Callovian beds east 
of Magindu station on the Tanganyika Central Railway. 

A second collection made by Miss M. McKinnon Wood from the coastlands of 
Kenya included material dealt with by Weir in a further paper (1938). The Kambe 



io JURASSIC BIVALVIA AND GASTROPODA 

Limestone, now definitely established by ammonites to include both Upper Bajocian 
and Bathonian horizons, was the source of most of the material in this collection, but 
there were also specimens from higher horizons of the Jurassic. Weir's paper 
included descriptions of the following new species : Nucula woodae [Kambe Lime- 
stone], Nucula (Pa/aeonitcula) gregoryi [Miritini Shales (Callovian)], Lopha krumbecki 
[Oxfordian-Kimmeridgian], Chlamys (Acqiiipecten) spathi [Kambe Limestone], 
Plesiopecten kenyana [Kambe Limestone], Lima (Pseudolimea?.) woodae [Kambe 
Limestone]. 

A series of bivalves and gastropods collected mainly from the locality Cud- 
Finagubi, about 3 miles S. of Mandera, in N.E. Kenya near the frontier with Somalia, 
formed the subject of a series of notes by Venzo (1942a, b, 1943, \^\a-c, 1945), 
followed by a larger memoir (Venzo 1949). About half the bivalves were identified 
(some with qualification) with previously described species and it was concluded 
that the age of the assemblage was Bathonian. Twenty species, a few with nume- 
rous named varieties, were described as new. Later field work has led to the con- 
clusion that the beds yielding this assemblage belong to a horizon very high in the 
Jurassic and that some of Venzo's specific identifications are to be queried. The 
age of the Cud Finagubi assemblage is discussed later in the present memoir (p. 24). 

Several reports of the Kenya Geological Survey published from 1952 onwards 
have included lists of Jurassic bivalves and gastropods, mainly from N.E. Kenya, 
based partly on identifications by the present writer, and in two of these (Saggerson 
& Miller 1957 ; Joubert i960) some of the specimens have been illustrated photo- 
graphically. Of publications of the Tanganyika Geological Survey, particular 
reference must be made to the Bulletin by Aitken (1961) dealing with the Mandawa- 
Mahokondo area of southern Tanganyika. This work includes a statistical study 
of African specimens of the trigoniid subgenus Indotrigonia, which comprises Tri- 
gonia smeei J. de C. Sowerby and related species. Aitken concludes that the true 
T. smeei, which, as already mentioned, occurs typically in India in beds of Oxfordian 
age, has not yet been found in East Africa, and that the common species of the 
Upper Kimmeridgian beds at Tendaguru is a distinct form to which he assigns the 
name Trigonia {Indotrigonia) africana. The following other trigoniids are also 
described in the same paper: Trigonia (Indotrigonia) mandawae sp. nov. [Lower to 
Upper Kimmeridgian], T. (I.) beyschlagi Muller [" Tithonian "], T. (I.) robusta sp. 
nov. [" Tithonian "], T. (I.) v-striata sp. nov. [" Tithonian "], T. (Trigonia) tangany- 
icensis sp. nov. [Middle or Upper Kimmeridgian], Laevitrigonia curta sp. nov. 
' Tithonian "], Opisthotrigonia curvata sp. nov. [" Tithonian "]. In addition, many 
bivalve species belonging to other families are listed from various horizons. 

Ill EAST AFRICAN JURASSIC BIVALVE AND GASTROPOD FAUNAS 
AND THEIR CHARACTERISTICS 

Liassic Assemblage 

The oldest beds anywhere in Kenya or Tanganyika assignable on fossil evidence to 
the Jurassic system are limestones exposed at Didimtu Hill, 2 miles N.E. of Bur 
Mayo, in N.E. Kenya. These beds are separated from the ancient rocks of the 



FROM TANGANYIKA AND KENYA n 

Basement System by the Mansa Guda formation (Ayers 1952 : 6 ; Thompson & 
Dodson i960 : 15), a series of sandstones and conglomerates, some 1300 feet in 
thickness, which so far have yielded no fossils. The Mansa Guda formation may be 
the equivalent of the Lugh Series of Stefanini, consisting of some 400 ft. of sand- 
stones, marls and limestones developed to the east, in Somalia. Stefanini (1932) 
recorded a small mussel-like bivalve and a naticiform gastropod from these beds 
and thought that their age might be Lower Liassic. The fossils are not, however, 
diagnostic and might equally well be of Triassic age. In the coastal area of southern 
Kenya the Duruma formation, except for part or all of its top division, the Mazeras 
Sandstones, is probably of much the same age as the Mansa Guda formation. In 
Tanganyika the Jurassic rocks are underlain by beds of the Karroo System. There 
is at present no fossil evidence that the Karroo beds extend above the Trias. 

The Lower Toarcian Didimtu Beds of N.E. Kenya were discovered by P. E. Kent 
and F. M. Ayers in 1951 and first recorded by the latter (Ayers 1952 : 9). They 
have been described in more detail by Thompson & Dodson (i960 : 20), who quote 
(: 22) a preliminary report on the Bivalvia and Gastropoda by the present writer. 
These fossils are described in the present work and listed on p. 189. Of the 30 
named species now recorded from Didimtu, 22 are described as new and eight (one 
with the qualification " aff. ") are referred to forms described previously, one of 
which is re-named. Seven of these are also known from Europe. The eighth, 
Weyla ambongoensis, a representative of the Pectinidae, was originally described 
from Madagascar and is also found in Pakistan and Morocco. It affords somewhat 
meagre evidence that a faunal sub-province comprising the western part of the 
present Indian Ocean region and extending over northern Africa had come into 
existence. Affinities with the Lias of Morocco are also indicated by the occurrence 
of the new gastropod genus Africoconulus, the type-species of which occurs in the 
Domerian of that country. The Didimtu fauna includes a rather larger assemblage 
of Toarcian gastropods and bivalves than the contemporaneous fauna from Mada- 
gascar described by Thevenin (1908ft), which consisted of 18 bivalves and two gastro- 
pods. 

Bajocian Assemblages 

The Upper Bajocian age of beds included in the Kambe Series, developed in the 
coastal district of Kenya, was established on the basis of ammonites collected by 
Miss M. McKinnon Wood. The bivalves and gastropods from her collections, 
amounting to 22 and two species respectively (some, however, identified only generic- 
ally), were described by Weir (1930, 1938). No specimens from these beds have been 
examined in the course of the present work. The Kambe Limestone is, however, 
underlain by the Mazeras Sandstones, yielding fossil wood considered by its most 
recent students to be Upper Triassic in age (Caswell 1956 : 16), although it was 
thought that the upper limit of the Sandstones might lie within the Lower Jurassic 
(Caswell 1953 : 17 ; 1956 : 17 ; Williams 1962 : 10). A sample of hard sandstone 
belonging to this formation and found at the locality Ribe, about 9 miles N.E. of 
Mazeras, has yielded a small series of gastropod moulds, one of which is described in 



i-> JURASSIC BIVALVIA AND GASTROPODA 

the present work as Cirrus mazerasensis sp. no v. Unfortunately, this material is in- 
sufficient to establish the geological age of the sample, but it is improbable that it is 
pre- Jurassic in view of the rareness of Cirrus in rocks older than the Lias. It is 
suggested that a Bajocian age may be assigned to the sample until further evidence 
is forthcoming. 

Bajocian depcsits occur along the Tanganyika Central Railway between Ngeren- 
gere in the west and a point between Kidugallo and Magindu in the east, but it is 
still uncertain where to draw their upper limit. They also crop out in the area to 
the north and south. The geology of this district was described by Hennig, who 
distinguished (1924 : 114, 121) between the Ngerengere Beds, continental deposits 
belonging to the Karroo System and thought by him to be Liassic in age, and the 
Ruvu Beds, which he considered to range from the Aalenian to the Oxfordian. No 
specimens from "Reek's fossil bed" (see p. 8), thought to be the lowest fossiliferous 
horizon of the local Jurassic series, have been examined in the course of the present 
work. That the Lower Bajocian (Aalenian) is represented in this area is shown by 
Arkell's (1956 : 330) record of ammonites of this age in carboniferous shales en- 
countered in boreholes in search of limestone north of Kidugallo. Some bedding 
planes of these shales are covered with specimens of the bivalve Bositra buchi 
(Roemer) [ = Posidonia ornati Quenstedt]. The " Posidonia " from Kissemo, N. of 
Kidugallo, recorded by Hennig (1924 : 43), may have come from about the same 
horizon. The Kidugallo Oolite, a formation overlying " Reek's fossil bed " and also 
included by Hennig in his Lower Ruvu Beds, yielded a number of Pectinidae and 
other molluscs recorded by Hennig (1924 : 14-20), but no fossils from this horizon 
have been seen by the present writer. Some molluscs now described came, however, 
from two small quarries north of Ngerengere Station, where the horizon is close to 
the junction of gneiss and sediment and probably fairly low in the local succession of 
fossiliferous Jurassic rocks. The bivalves include the species Eomiodon baroni 
(Newton) and Bakevellia iraonensis (Newton), both originally described from Mada- 
gascar, the former from the Bathonian, the latter from Middle Jurassic beds the 
precise age of which has not hitherto been recorded. 

Hennig's Middle Ruvu Beds and the Station Beds of King (1954 : 15) are approxi- 
mately synonymous. Aitken (in Quennell ct al., 1956 : 180-181) has compiled a 
list of their fossils as recorded by Hennig. The majority are probably of Bathonian 
age, but those from the more easterly localities (Hennig 1924 : 50-55) may be from 
the Bathonian. Of the molluscs described in the present work, it is most probable 
that, in addition to those from near Ngerengere, specimens localized as Kidugallo 
and as 6 miles N.W., 5 miles N.W., 2$ miles N.N.W., i| miles N.N.W., and i\ miles 
E. of that place are all of Bajocian age. The full list of Bajocian species definitely 
identified from this area in the course of the present work is, therefore, as follows : 

Modiolus anatiniis (Smith) 

Bositra buchi (Roemer) 

Bakevellia iraonensis (Newton) 

Lopha gregarea (J. Sowerby) 

Trigonia costata Parkinson 



FROM TANGANYIKA AND KENYA 13 

Trigonia kenti sp. nov. 

Trigonia kidngalloensis sp. nov. 

Lucina despecta Phillips 

Fimbria kidngalloensis sp. nov. 

Pronoella kidngalloensis sp. nov. 

Eotrapezium ? kenti sp. nov. 

Eomiodon baroni (Newton) 

Eomiodon tanganyicensis sp. nov. 

Corbula eamesi sp. nov. 

Pholadomya lirata (J. Sowerby) 

Goniomya trapezicostata (Pusch) 

Osteomya dilata (Phillips) 

Pseudomelania (Oonia) kidngalloensis sp. nov. 

Coelostylina stockleyi sp. nov. 

Ataphrns aff. acmon (d'Orbigny) 

Beds which are probably Bajocian in age (although ammonite evidence on this 
point is lacking) are also well developed towards the southern end of the Jurassic 
outcrop, in the area N.W. of Lindi. They consist largely of shales (the Pindiro 
Shales of Hennig) but there are also limestone bands and layers of limestone nodules. 
The shales, yielding numerous small molluscs, were encountered in trial borings for 
oil near Mandawa. The following list of species described in the present work 
supplements (or most probably in part replaces) Hennig's records of the species 
found in these shales, which have been quoted by Aitken (in Ouennell et al., 1956 : 

175) : 

Parallelodon pindiroensis sp. nov. 

Modiolus imbricatus (J. Sowerby) 

Gervillella orientalis (Douville) 

Pinna buchii Koch & Dunker 

Astarte pindiroensis sp. nov. 

Astarte kenti sp. nov. 

Protocardia bipi sp. nov. 

Protocardia besairiei sp. nov. 

Mactromya eamesi sp. nov. 

Pronoella pindiroensis sp. nov. 

Pronoella putealis sp. nov. 

Corbula mandawaensis sp. nov. 

Corbula pindiroensis sp. nov. 

Corbula tanganyicensis sp. nov. 

Ceratomya tanganyicensis sp. nov. 

Thracia lens (Agassiz) 

Coelostylina mandawaensis sp. nov. 

Zygopleura mandawaensis sp. nov. 

Procerithium (Rhabdocolpus) mandawaense sp. nov. 

Exelissa africana sp. nov. 



M JURASSIC BIVALVIA AND GASTROPODA 

Vietteia mandaivaensis sp. nov. 
Pietteia stockleyi sp. nov. 
Pictavia tanganyicensis sp. nov. 
Ampullospira besairiei sp. nov. 

All except four of the species in the above list are new, and not one occurs in rocks 
regarded as Bajocian in S.E. Kenya or in the Kidugallo district of Tanganyika. 
Hennig (1917), however, recorded Gervillia aff. iraonensis Newton from the Pindiro 
Shales and the species in question, Bakevellia iraonensis, is here recorded from Bajo- 
cian beds at Ngerengere, west of Kidugallo. The four previously described species 
in the above list from the Pindiro Shales include Pinnabuchii, Thracia lens and Modio- 
lus imbricatus, all of which occur in Europe in both the Bajocian and the Bathonian, 
the third (as in East Africa also) ranging up into much later beds. The fourth 
species, Gervillella orientalis, was originally described from the Moghara massif of 
Sinai, where it is known from later collecting to occur in beds of undoubtedly 
Bathonian age. On the other hand, one of the species of the Pindiro Shales now 
described as new, Ampullospira besairiei, occurs in beds in Madagascar known to be 
Bajocian in age. It would thus appear that the palaeontological evidence as to 
whether the Pindiro Shales should be referred to the Bajocian or to the Bathonian 
is still inconclusive. 

Bathonian Assemblages 

Uncertainty about exact delimitation of Bathonian beds from those of earlier and 
later stages exists throughout East Africa (cf. Aitken 1961 : 17-19), and none of 
the Mollusca from Tanganyika here described can be unhesitatingly referred to this 
stage. It is, however, probable that specimens of Liostrea dubiensis (Contejean) 
from 1 mile and 2 miles west of Magindu Station, on the Tanganyika Central Rail- 
way, are from the Bathonian. In the Rahmu area of N.E. Kenya the Murri Lime- 
stones of Thompson & Dodson (1958 : 15) are considered to be largely or entirely 
Bathonian in age, and have yielded the three species Brachidontes (Arcomytilns) 
aspcr (J. Sowerby), Chlamys curvivarians (Dietrich) and Lima (Plagiostoma) biinien- 
sis sp. nov., as recorded in the present memoir. Further species from those lime- 
stones have been recorded by Weir (1929), and also by Ayers (1952 : 27) on the basis 
of identifications by J. A. Douglas, and are listed by Thompson & Dodson (1958 : 
19). Some of the determinations in question, for example, of the Oxfordian species 
Cercomya siliqua Agassiz and Exogyra fourtaui Stefanini, appear suspect. 

The most interesting assemblage from beds of approximately Bathonian age in 
N.E. Kenya is that from the Asaharbito Beds of Thompson & Dodson (1958 : 21). 
Not all the provisional identifications originally cited have been confirmed, and the 
following revised list from this horizon (omitting forms identified only generically) 
can now be presented : 

Grammatodon sublaevigatus (Zieten) 

Liostrea dubiensis (Contejean) 

Trigonia cf. brevicostata Kitchin 

Astarte ayersi sp. nov. 



FROM TANGANYIKA AND KENYA 15 

Sphaeriola madridi (d'Archiac) 
Corbula asaharbitensis sp. nov. 
Cuspidaria ayersi sp. nov. 

Unfortunately, the Asaharbito Beds have yielded no ammonites and on the basis 
of the assemblage listed above it is not possible to say anything more definite than 
that they are of Bathonian or Callovian age. The Grammatodon and Sphaeriola, 
both species found in Europe, suggest a Bathonian age, but Trigonia brevicostata 
occurs in India in the Callovian. Liostrea dubiensis is a widely distributed species 
with an extended geological range. So far, the two species most characteristic of 
the Bathonian rocks of Madagascar and N.W. India, Protocardia grandidieri (Newton) 
and Corbula lyrata J. de C. Sowerby, have not been reported from East Africa. 
Most of the previously described species identified in the Bathonian of this area have 
also been found in Europe. Chlamys curvivarians (Dietrich), however, a form with 
an extended geological range, is known only from E. and N.E. Africa, Arabia and 
India. 

Callovian Assemblages 

Callovian rocks are well developed in Tanganyika and Kenya, but in this case 
also it is not yet possible to determine exactly their upper and lower limits in the 
field. Aitken (1961 : 19-27) has compiled a list of the Mollusca recorded by earlier 
workers and collected by himself in beds in S.E. Tanganyika belonging to the "Upper 
Bathonian-Oxfordian " part of his Mandawa-Mahokondo Series and has indicated 
which of these are probably from the Callovian. The following list of Bivalvia and 
Gastropoda from the Callovian of this area is based on material examined by the 
present writer and on Aitken's records, marked with an asterisk in the case of species 
not represented in this material (the " Ceromyopsis sp." of Aitken is here identified 
as Cer atomy opsis basochiana (Def ranee)) : 

Grammatodon (Indogrammatodon) virgatus (J. de C. Sowerby) 
*Lycettia indica Cox 
*Modiolus glendayi Weir 
Eopecten anbryi (Douville) 
Entolium corneolum (Young & Bird) 
Chlamys (Spondylopectenl) badiensis Cox 
*Trigonia prora Kitchin 
Trigonia elongata J. de C. Sowerby 
*Trigonia aff. propinqua Kitchin 
*Myophorella (Orthotrigonia) cf. katchensis (Kitchin) 
* Astarte muelleri Dacque 
Astarte unilateralis J. de C. Sowerby 
Astarte aitkeni sp. nov. 
*Ceratomya concentrica (J. de C. Sowerby) 
*Ceratomya cf. wimmisensis (Gillieron) 
*Ceratomyopsis basochiana (Defrance) 
*Tellnrimya tellnris (Lamarck) 



n. JURASSIC BIVALVIA AND GASTROPODA 

Thracia viceliacensis d'Orbigny 
Pseudorhytidopilus lonjiensis sp. now 
Pseudomelania aspasia (d'Orbigny) 
Bourguetia saemanni (Oppel) 
Harpagodes aff. oceani (Brongniart) 
Ampullospira quennclli sp. nov. 
Akera tanganyicensis sp. nov. 

According to Hennig's (1924 : 56) profile, Callovian beds are exposed along the 
Central Railway in Tanganyika in the cuttings from about 2 km. to nearly 4 km. 
east of Magindu Station, but he ignored the fact that Kinkelin's Callovian fossils, 
described by Dacque (1910), came from very close to Magindu Station (see p. 7). 
As summarized by Aitken {in Quennell et al., 1956 : 180), Hennig (1924 : 57-92) 
recorded a number of molluscan species from these beds, but some of the determina- 
tions need revision. The following Callovian species from this part of the railway 
are recorded in the present memoir : 

Liostrea (Catinida) alimena (d'Orbigny) 

Trigonia (Frenguelliella) tealei Cox 

A start e mnelleri Dacque 

Ceratomyopsis basochiana (Defrance) 

Ceratomya pittieri (de Loriol) 

Pholadomya lirata (J. Sowerby) 

To these may be added the following species, obtained from rocks of about the 
same age in the district south of Tarawanda, north of Magindu : 
Grammatodon (1 ndogrammatodon) stockleyi Cox 
Meleagrinella echinata (Smith) 
Chlamys subtextoria (Miinster) 
Protocardia consobrina (Terquem & Jourdy) 
Neritoma (Neridomns) aff. gea (d'Orbigny) 

At localities near Tanga, in the extreme N.E. of Tanganyika, Callovian beds 
yielded the following species : 

Grammatodon (I ndogrammatodon) virgatus (J. de C. Sowerby) 

Modiolus bipartitus J. Sowerby 

Oxytoma inequivalvis (J. Sowerby) 

Chlamys (Spondylopecten?) badiensis Cox 

Trigonia [Frenguelliella) tealei Cox 

Goniomya trapezicostata (Pusch) 

In N.E. Kenya, at localities near the Daua river, the Rukesa Shales of Joubert 
(i960 : 13) are dated as Callovian on the evidence of a nautiloid cephalopod referred 
to Paracenoceras and of the bivalve assemblage. The presence of Eligmus rollandi 
Douville suggests that the succeeding Muddo Erri Limestones are at least in part not 
later than Callovian, although brachiopod evidence has been considered to indicate 
that these beds extend upwards into the Lower Oxfordian. Joubert (i960 : 14-15, 
17 18) has compiled lists of molluscs and other invertebrates which have been cited 



FROM TANGANYIKA AND KENYA 17 

from these formations. Species represented in the collections examined by the pre- 
sent writer may be listed as follows (R, Rukesa Shales ; ME, Muddo Erri Lime- 
stones) : 

Brachidontes (Arcomytilus) asper (J. Sowerby). ME 

Brachidontes (Arcomytilus) laitmairensis (de Loriol). ME 

Eligmus rollandi Douville. ME 

Entolium corneolum (Young & Bird). ME 

Eopecten aubryi (Douville). R, ME 

Camptonectes auritus (Schlotheim). ME 

Chlamys curvivarians (Dietrich). R, ME 

Lima (Plagiosioma) cf. schardti de Loriol. R, ME 

Lima (Plagiostoma) cf. jumaraensis Cox. ME 

Lima (Plagiostoma) muddoensis sp. nov. ME 

Pseudolimea duplicata (J. de C. Sowerby). ME 

Lopha costata (J. de C. Sowerby). R, ME 

Lopha gregarea (J. Sowerby). R, ME 

Liostrea (Catinida) alimena (d'Orbigny). R, ME 

Lucina cf. lirata Phillips. ME 

Mactromya aequalis Agassiz. R, ME 

Cer atomy opsis basochiana (Defrance). R, ME 

Anisocardia minima (J. Sowerby). R 

Pholadomya lirata (J. Sowerby). R 

Pholadomya ovalis (J. Sowerby). ME 

Homomya inornata (J. de C. Sowerby). R 

Cer atomy a concentrica (J. de C. Sowerby). R, ME 

Cer atomy a wimmisensis (Gillieron). ME 

If these lists of Callovian species are examined it would appear that the East African 
assemblages during that stage differed less from those living contemporaneously in 
Europe than during the Bajocian and Toarcian. The number of species, whether 
new or previously described, unknown from Europe is relatively small. Previously 
described species in these lists known only from East Africa are Grammatodon 
(Indogrammatodon) stockleyi, Trigonia (Frenguelliella) tealei and Astarte muelleri. 
Species common to India and East Africa but unknown from Europe are Grammato- 
don (Indogrammatodon) virgatus, Lycettia indica, Modiolus glendayi, Eopecten aubryi, 
Chlamys curvivarians, Chlamys (Spondylopectenl) badiensis, Trigonia prora, and 
Astarte unilateralis (omitting those forms of which the identifications are qualified). 
The incoming of the subgenus Indogrammatodon, abundant in this region as well as 
in Arabia and N.W. India but unknown in Europe, may be particularly noted at this 
stage. 

Oxfordian Assemblages 

Aitken (1961 : 21) has listed a series of ammonites which establish the Upper 
Oxfordian age of part of the succession in the area of southern Tanganyika dealt 
with in his paper, but the only identified bivalve species collected by him at one of 



18 JURASSIC BIVALVIA AND GASTROPODA 

the same localities seems to be Grammatodon (Indogrammatodon) virgatus (J. de C. 
Sowerby). Material from the same area collected by geologists of the British 
Petroleum Company Ltd. includes a number of bivalves and gastropods stated to 
come from Upper Oxfordian beds. These may be listed as follows : 

Eopecten anbryi (Douville) 

Pseudolimea mandawaensis sp. nov. 

Liostrea polymorpha (Munster) 

Astarte sowerby ana Holdhaus 

Pholadomya hemicardia Roemer 

Plenromya calceiformis (Phillips) 

Aitken's locality WA. 1817, which he informs me is probably Upper Oxfordian, 
has yielded the gastropod recorded herein as Nerinella hnuelleri Cox, associated with 
Grammatodon {Indogrammatodon) virgatus and an indeterminate perisphinctid 
ammonite. 

Ammonite-bearing Oxfordian beds in the Bagamoyo hinterland of Tanganyika 
have yielded the following species, as also recorded in the present memoir : 
Grammatodon {Indogrammatodon) stockleyi Cox 
Pteria tanganyicensis sp. nov. 
Meleagrinella radiata (Trautschold) 
Entolium corneolum (Young & Bird) 
Limatula moorei sp. nov. 
Gryphaea hennigi Dietrich 
Trigonia {Frenguelliella) tealei Cox 
Astarte episcopalis de Loriol 
Fimbria quennelli sp. nov. 
Pleuromya uniformis (J. Sowerby) 
Goniomya liter ata (J. Sowerby) 
Bourguetia saemanni (Oppel) 

No extensive collections of Oxfordian bivalves have yet been made in the coastal 
area of Kenya, although a few species were recorded by Weir in the Hunterian 
Museum Monographs. In the Taj abba- Wergudud area of N.E. Kenya Saggerson & 
Miller (1957 : 13) have referred to the Oxfordian a series of pink and yellow fossili- 
ferous limestones to which they have given the name Golberobe Beds. Unfortunate- 
ly, however, there is no ammonite evidence for the exact dating of these deposits. 
Bivalves from these beds which have been named specifically and are dealt with in 
the present memoir are as follows : 

Modiolus imbricatus (J. Sowerby) 

Modiolus {Inoperna) sowerbianus (d'Orbigny) 

Mytilus {Falcimytilus) tifoensis sp. nov. 

Mytilus {Falcimytilus) dietrichi sp. nov. 

Brachidontes {Arcomytilus) laitmairensis (de Loriol) 

Gervillia saggersoni sp. nov. 

Gervillella siliqua (Eudes-Deslongchamps) 



FROM TANGANYIKA AND KENYA 19 

Meleagrinella radiata (Trautschold) 
Lopha solitaria (J. de C. Sowerby) 
Lopha tifoensis sp. nov. 
Liostrea dubiensis (Contejean) 
Exogyra nana (J. Sowerby) 
Mactromya quadrata (Roemer) 
Corbida kailtaensis sp. nov. 

Of the above species, Meleagrinella radiata occurs in abundance at one horizon. 
Further north, near the Daua river, the Rahmu Shales of Joubert (i960 : 19) are 
referred to the Oxfordian on ammonite evidence and have yielded the following 
bivalves, as now identified : 

Mytilus (Falcimytilus) jurensis Roemer 

Camptonectes auritus (Schlotheim) 

Lima (Plagiostoma) rahmuensis sp. nov. 

Lopha gregarea (J. Sowerby) 

Lopha solitaria (J. de C. Sowerby) 

Lopha cf. intricata (Contejean) 

Exogyra nana (J. Sowerby) 

Protocardia rahmuensis sp. nov. 

Homomya rahmuensis sp. nov. 

The succeeding Seir Limestones of Joubert (i960 : 20) have been dated as at least 
in part Upper Oxfordian (transversarium Zone) on ammonite evidence, although it 
is thought that their upper part may belong to the Lower Kimmeridgian. It is 
probable that all of the following forms dealt with in the present memoir, which are 
mainly from the Wilderri Hill and Dusse localities, are from the Oxfordian part of 
the limestones : 

Grammatodon (Indogrammatodon) stockleyi Cox 

Grammatodon {Indogrammatodon) irritans (Hennig) 

Mytilus (Falcimytilus) jurensis Roemer 

Stegoconcha gmuelleri (Krenkel) 

Meleagrinella radiata (Trautschold) 

Entolium corneolum (Young & Bird) 

Camptonectes auritus (Schlotheim) 

Eopecten thurmanni (Brauns) 

Eopecten aff. albus (Quenstedt) 

Chlamys (Radulopecten) inaequicostata (Young & Bird) 

Pseudolimea duplicata (J. de C. Sowerby) 

Lopha gregarea (J. Sowerby) 

Lopha solitaria (J. de C. Sowerby) 

Liostrea dubiensis (Contejean) 

Astarte huralensis Stefanini 

Ceratomya wilderriensis sp. nov. 

Mactromya quadrata (Roemer) 

Pseudomelania (Rhabdoconcha) wilderriensis sp. nov. 



20 JURASSIC BIVALVIA AND GASTROPODA 

Bourguetia saemanni (Oppel) 
Pietteia dusseensis sp. nov. 
Ampullospira dejanira (d'Orbigny) 
Globularia phasianelloides (d'Orbigny) 
Nerinella cutleri sp. nov. 

Species known to occur in Europe in beds belonging to the same stage predominate 
in these Oxfordian assemblages. The number of forms described as new is not large, 
and previously described species known only from East Africa consist merely of 
Grammatodon (Indogrammatodon) stockleyi, Trigonia (Frenguelliella) tealei and 
Astarte huralensis. Species common to East Africa and India but unknown from 
Europe are Grammatodon (Indogrammatodon) virgatus, Astarte sow erby ana, Eopecten 
aubryi, Gryphaea hennigi and Stegoconcha gmuelleri. The subgenus Indogramma- 
todon continues to be well represented. 

Kimmeridgian Assemblages 

In the area of southern Tanganyika dealt with in his memoir Aitken (1961 : 24-31) 
distinguishes between the Septarian Marl, yielding Lower Kimmeridgian ammonites 
(perhaps also Upper Oxfordian ones at the base of the formation) and the Tendaguru 
Series, the lower part of which is classified as Middle-Upper Kimmeridgian and the 
upper part as Upper Kimmeridgian-Tithonian. Aitken (1961 : 29) suggests that the 
marine beds at Tendaguru itself all belong to the last of these divisions. 

The same worker (1961 : 25-26) has compiled a list of bivalves found in the 
Septarian Marl based on the records of German workers. No specimens from this 
formation have been examined in the course of the present work. He has also 
recorded six named species and a number of forms identified only generically from 
his Middle-Upper Kimmeridgian division of the Tendaguru Series. No bivalves 
from this division have been examined in the course of the present work, but the 
following gastropods from Dr. Aitken's collection are described : 

Bathrotomaria aitkeni sp. nov. 

Lissochilus stremmei Dietrich 

Pseudomelania vittata (Phillips) 

Pseudomelania (Oonia) aitkeni sp. nov. 

Globularia aff. phasianelloides (d'Orbigny) 

Pseudonerinea clio (d'Orbigny) 

Nerinella mandawaensis sp. nov. 

The presence of Pseudonerinea clio at this horizon is in keeping with its known 
occurrences in Europe, but the presence of Pseudomelania vittata, a Cornbrash species 
in Europe, in the Kimmeridgian of East Africa, is worthy of comment. As now 
suggested in the discussion of this species, it is, however, possible that the distinc- 
tions drawn between it and certain related but supposedly distinct species by 
European workers are of no significance. 

The following is a combined list of the species now recorded from the " Upper 
Kimmeridgian-Tithonian " division of Aitken's Tendaguru Series in the Mandawa- 






FROM TANGANYIKA AND KENYA 

Mahokondo area (M) and in the Tendaguru area (T) : 

Grammatodon (Indogrammatodon) irritans (Hennig). T 

Grammatodon [Indogrammatodon) matapwaensis sp. nov. T 

Apolinter kindopeensis sp. nov. T 

Cucullaea kipandeensis sp. nov. T 

Lithophaga suboblonga Dietrich. T 

Modiolus bipartitus (J. Sowerby). T 

Modiolus (Inoperna) perpiicatus (Etallon). T 

Mytilus (Falcimytilus) dielrichi sp. nov. T 

Brachidontes (Arcomytilus) laitmairensis (de Loriol). M 

Musculus kindopeensis sp. nov. T 

Gervillella aviculoides (J. Sowerby). T 

Pinna constantini de Loriol. T 

Stegoconcha gmuelleri (Krenkel). T 

Oxytoma inequivalvis (J. Sowerby). T 

Meleagrinella radiata (Trautschold). T 

Bositra somaliensis (Cox). T 

Entolium corneolum (Young & Bird). T 

Chlamys matapwaensis sp. nov. M 

Chlamys (Radulopecten) kinjeleensis sp. nov. T, M 

Lima (Acesta) kindopeensis sp. nov. T 

Lima {Acesta) cutleri sp. nov. T 

Pseudolimea duplicata (J. de C. Sowerby). T 

Limatula migeodi sp. nov. T 

Lopha hennigi (Dietrich). T 

Lopha? kindopeensis sp. nov. T 

Liostrea dubiensis (Contejean). T 

Exogyra nana (J. Sowerby). T 

Trigonia migeodi sp. nov. T 

Trigonia (Indotrigonia) africana Aitken [smeei auct.]. T 

Trigonia (Indotrigonia) dietrichi Lange. T 

Myophorella kiwawaensis sp. nov. M 

Laevitrigonia dwanika sp. nov. T 

Opisthotrigonia curta (Aitken). M 

Hippopodium quenstedti (Dietrich). T 

Astarte subobovata Dietrich. T 

Astarte recki Dietrich. T 

Astarte sowerby ana Holdhaus. T 

Astarte weissermeli Dietrich. M, T 

Astarte mandawaensis sp. nov. M 

Astarte lonjiensis sp. nov. M 

Astarte mitoleensis sp. nov. M 

Coelastarte dietrichi sp. nov. T 

Seebachia janenschi Dietrich. M 



JURASSIC BIVALVIA AND GASTROPODA 

Lucina cutleri sp. nov. T 

Sphaera subcorrugata Dietrich. T 

Protocardia schencki Miiller. T 

Protocardia suprajurensis (Contejean). M 

Protocardia (Tendagurium) propebanneiana (Dietrich). T 

Anisocardia kinjeleensis sp. nov. T 

Eomiodon dinosaurianum sp. nov. T 

Eomiodon (Africomiodon) cutleri sp. nov. T 

Homomya hortulana Agassiz. T 

Pleuromya uniformis (J. Sowerby). T 

Nummocalcar mitoleensis sp. nov. M 

Scurriopsis (Dietrichiella) kindopensis (Dietrich). T 

Chrysostoma staffi Dietrich. T 

Lissochilus stremmei Dietrich. T 

Chartronella mitoleensis sp. nov. M 

Pseudomelania (Oonia) dietrichi sp. nov. T 

Purpuroidea aff. gigas (Thurmann & Etallon). M 

Paracerithium lonjiense sp. nov. M 

Cossmannea hennigi (Dietrich). T 

Nerinella cutleri sp. nov. T 

South of the Daua river, in N.E. Kenya, the Hereri Shales of Joubert (i960 : 24) 
are referred to the Kimmeridgian mainly on stratigraphical grounds, as no ammonites 
identifiable with certainty have been found in them. The following species from 
Hereri are recorded in the present work : 

Grammatodon (Indogrammatodon) irritans (Hennig) 

Mytilus (Falcimytilus) jurensis Roemer 

Eopecten thurmanni (Brauns) 

Chlamys curvivarians (Dietrich) 

Exogyra nana (J. Sowerby) 

Protocardia {Tendagurium) bannesiana (Contejean) 

Cer atomy op sis striata (d'Orbigny) 

Ceratomya excentrica (Roemer) 

Bourguetia saemanni (Oppel) 

The presence of Protocardia bannesiana appears, from its known European 
occurrences, to confirm the Kimmeridgian age of the above assemblage. 

In the same area the succeeding Dakacha Limestones are considered by Joubert 
(i960 : 28) as " probably bridging the uppermost Kimmeridgian and the lowest part 
of the Tithonian ", thus being approximately contemporaneous with the dinosaur 
beds of Tendaguru. No ammonites have been found in them, but they have 
yielded the following bivalves and gastropods, described in the present work : 

Nuculoma (Palaeonucula) bellozanensis sp. nov. 
Modiolus virgulinus (Thurmann & Etallon) 
Modiolus (Inoperna) perplicatus (Etallon) 



FROM TANGANYIKA AND KENYA 23 

Chlamys curvivarians (Dietrich) 

Lima (Plagiostoma) sublaeviuscula Krumbeck 

Ctenostreon proboscideum (J. Sowerby) 

Lopha gregarea (J. Sowerby) 

Rutitrigonia stefaninii (Venzo) 

Mactromya quadrata (Roemer) 

Quenstedtia jouberti sp. nov. 

Ceratomya excentrica (Roemer) 

Pholadomya hemicardia Roemer 

Harpagodes thirriae (Contejean) 

Globularia hemisphaerica (Roemer) 

Globularia hennigi sp. nov. 

Trochalia depressa (Voltz) 
The assemblage listed above includes none of the characteristic trigoniids or other 
elements of the Tendagura fauna. The occurrence of such species as Modiolus 
virgulinus and Harpagodes thirriae, found apparently in the top bed of the Dakacha 
Limestones (Joubert 1960 : 27), suggests, from the known European occurrences of 
these species, that this bed is Kimmeridgian in age (even in the more restricted 
sense) and not later. The presence of Rutitrigonia stefaninii, however, serves as a 
link between this fauna and that of the beds at Cud Finagubi, discussed a little 
later, and is interesting as constituting the earliest known occurrence of Rutitrigonia. 
If the East African Kimmeridgian assemblages listed above are considered as a 
whole, it will be seen that, while, like those from lower horizons, they include a large 
number of species found in the Jurassic of Europe, they have an Indian element 
which is rather more pronounced than in the earlier faunas. Affinity with the Indian 
fauna is particularly marked among the trigoniids, as seen by the abundance (in 
southern Tanganyika) of Indotrigonia and by the presence there of Opisthotrigonia. 
Other forms common to the two areas but not found in Europe are Astarte sowerby ana 
Holdhaus and Stegoconcha gmuelleri (Krenkel). Indogrammatodon continues 
to be an important element of the African fauna, although the actual species of 
Kimmeridgian age here recorded are distinct from those found in India. The only 
known post-Liassic occurrence of the genus Hippopodium is in these East African 
beds, while it is interesting to find in the Upper Jurassic of this region the remarkable 
astartid genus Seebachia, otherwise known only from South Africa, where it occurs 
in the Neocomian. Quite a number of Kimmeridgian species, some here described 
as new and others described in earlier monographs by Miiller, Dietrich, Hennig and 
Aitken, have so far been found only in East Africa. 

In the extreme north-east of Kenya a series of beds is developed the age of which 
has given rise to some controversy. Termed by Dixey (1948 : 84) the Mandera 
Series, these beds have been described by Joubert (i960 : 31-39), who cites 
evidence from N.E. of Melka Dakacha that they succeed the Dakacha Limestones 
conformably. Some 40 ft. from the base of this series is a fossiliferous deposit 
(the basal bed of the subdivision termed by Joubert the Gudediye Beds) 
yielding the two bivalve species here described as Tancredia manderaensis sp. nov. 



24 JURASSIC BIVALVIA AND GASTROPODA 

and Myopholas manderaensis sp. nov. Some hundreds of feet higher (according to 
Joubert's reading of the succession), and separated from this bed by almost unf ossi- 
ferous deposits, are the Finaguba Beds, which are of interest to palaeontologists as 
yielding the assemblage monographed and regarded as of Bathonian age by Venzo 
(1949). No specimens from the locality Cud Finagubi itself (the source of most of 
Venzo's material) have been examined, but a short discussion on the age of this 
assemblage, based on his illustrations, may be appropriate at this point. 

The most abundant fossils are trigoniids, belonging to what I would regard as only 
two species, Trigonia dainellii Venzo (this includes specimens identified by Venzo 
as the Callovian species T. brevicostata Kitchin) and T. stefaninii Venzo. T. dainellii 
belongs to a subgenus of Trigonia which has not yet received a name but is represented 
in the Upper Jurassic of Europe by a species identified by de Loriol (1868 : 160, pi. 
10, figs. 12-16 ; 1872 : 295, pi. 16, fig. 20) as Trigonia truncata Agassiz. In the 
Yonne Department of France this species occurs (de Loriol 1868 : 252) only a few 
feet below the Cretaceous in beds which appear to be referable to the Portlandian 
(as restricted by British geologists), but in the Haute-Marne it occurs (de Loriol 
1872 : 498, 499) in beds which would be included in the Kimmeridgian in the British 
sense, while in northern Germany Credner (1863 : 22, 36) records it from well down 
in the Kimmeridgian. The similarity between T. dainellii and T. truncata, possibly 
amounting to the specific identity of the two forms, thus strongly suggests that the 
Finaguba Beds are Upper Jurassic (Kimmeridgian or Portlandian) in age. The 
second trigoniid, Trigonia [now Rutitrigonia] stefaninii Venzo, has already been 
commented upon when discussing the fauna of the Dakacha Limestones. Although 
belonging to a genus previously reported only from the Cretaceous, the presence of 
this species in N.E. Kenya in beds of which the Upper Jurassic age could not be 
disputed shows that it does not provide evidence for a Cretaceous age for the 
Finaguba Beds. Apart from the trigoniids and some small nondescript oysters, 
these beds yielded a large number of internal moulds of bivalve shells not all identifi- 
able with any certainty even generically. Venzo's application to these of the names 
of such Bathonian species as Eonavicula eudesii (Morris & Lycett), Anisocardia 
loweana (Morris & Lycett), Sphaera madagascariensis (Newton) and Quenstedtia 
morrisi (Cossmann) has no stratigraphical significance. The same remark applies 
to the identification of Grammatodon (Indogrammatodon) virgatus (J. de C. Sowerby) 
in this fauna. This subgenus Indogrammatodon is undoubtedly represented by more 
than one species, but it is not obvious what specific names should be applied to such 
poor material. My present view, taking into consideration the stratigraphical 
evidence adduced by Joubert, is that the Finaguba Beds are of Upper Kimmeridgian 
if not of still later Jurassic age. 

The beds of the Mandera Series are succeeded by deposits for which the term 
Marehan Series has been adopted (Saggerson & Miller 1957 : 23 ; Joubert i960 : 39). 
The lower of the two divisions of this series (the Danissa Beds) has been dated as 
Lower Cretaceous on palaeobotanical evidence which is not altogether convincing. 
A fossiliferous horizon in these beds has yielded a form (Trigonia dainellii Venzo) 



FROM TANGANYIKA AND KENYA 25 

already discussed and, limited though this evidence is, it favours the inclusion of 
the Danissa Beds, like the Mandera Series below them, in the Jurassic. 

IV SYSTEMATIC DESCRIPTIONS 

Class BIVALVIA Linnaeus 
Superfamily NUCULACEA 
Family CTENODONTIDAE Wohrmann 1893 
Genus PALAEONEILO Hall 1869 

Palaeoneilo asaharbitensis sp. nov. 
PI. 1, fig. 1 

Diagnosis. Of medium size for the genus (length of holotype 20 mm.), sub- 
elliptical, height about three-fifths of length ; moderately inequilateral, with the 
umbo near the anterior third of the length ; inflation rather strong for the genus. 
Umbo narrowly rounded, its outline continuous with the almost straight, gently 
sloping postero-dorsal outline of the shell ; antero-dorsal outline strongly excava- 
ted. Anterior margin broadly rounded, posterior margin more narrowly rounded, 
ventral margin strongly and nearly symmetrically convex. Details of ornament 
unknown. 

Holotype. No. L. 83864, the internal mould of a left valve. The only specimen. 

Locality and horizon, i mile N. of Asaharbito, N.E. Kenya ; Bathonian 
[? or Callovian], Asaharbito Beds. 

Remarks. The muscle scars and pallial line are not seen in the holotype, and 
impressions of taxodont teeth, while clearly visible along the postero-dorsal and 
antero-dorsal margins, are obscured immediately below the umbo. Hence the 
reference of the species to the genus Palaeoneilo is based on its general morphology. 
The most closely comparable form described from the Middle or Upper Jurassic is 
P. longiuscula (de Loriol) (1899 : 159, pi. 10, figs. 23-25, ex Merian MS.), Lower 
Oxfordian of Switzerland, which is slightly more elongate. 

Family NUCULIDAE 

Genus NUCULOMA Cossmann 1907 

Subgenus PALAEONUCULA W. Quenstedt 1930 

Nuculoma (Palaeonucula) bellozanensis (de Loriol) 
PI. 1, figs. 3a, b 

1875. Nucula bellozanensis de Loriol : 138, pi. 17, figs. i6a-c. 
Material. One specimen (no. L.92293). 



26 JURASSIC BIVALVIA AND GASTROPODA 

Locality and horizon. 2 miles S. of Melka Dakacha, N.E. Kenya ; Upper 
Kimmeridgian, Dakacha Limestones. 

Remarks. This small, evenly ovate specimen, which is just under 10 mm. long, 
agrees so well in size and shape with de Loriol's figures of N. bellozanensis that there 
seems no reason to qualify its identification. Of other comparable species, Nucula 
saxatilis Contejean (i860 : 284, pi. 21, fig. 13), from the Kimmeridgian of the French 
Jura, is less elongate. Nucula ornati Quenstedt (1851 : 528, pi. 44, fig. 7), which, if 
Quenstedt's conception of the species is accepted, ranges in Europe from the Upper 
Bajocian to the Oxfordian, has a slightly more prominent umbo. De Loriol's types 
of N. bellozanensis were from the Lower Kimmeridgian of northern France. 

I follow Van de Poel (1955) in regarding Palaeonucula as a subgenus of Nuculoma 
rather than of Nucula. 



Family NUCULANIDAE 

Genus NUCULANA Link 1807 

Subgenus DACRYOMYA Agassiz 1840 

Nuculana (Dacryomya) thompsoni sp. nov. 
PL 1, figs. 4a, b, c 

Specific name. After Mr. A. O. Thompson, of the Geological Survey of Kenya, 
collector of the holotype. 

Diagnosis. Small (length of holotype 8-6 mm.), pyriform, height two-thirds of 
length ; gibbose ; with strongly opisthogyrous, submedian umbones and a short 
posterior rostrum the narrow extremity of which is slightly below mid-height. 
Postero-dorsal outline strongly concave ; escutcheon broad, cordate, well impressed, 
bordered by umbonal ridges. Antero-dorsal outline and anterior and antero-ven- 
tral margins forming an uninterrupted, parabolic curve ; posterior end of ventral 
margin almost straight. Surface, except for the smooth escutcheon, ornamented 
with regular concentric threads, the tops of which are about 0-2 mm. apart. 

Holotype. No. LL. 35000. The only specimen. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. Nuculana zieteni (Brauns) (1871 : 373) (non d'Orbigny sp.), Middle 
Lias of Europe, is less gibbose and has its posterior rostrum accentuated by a sinus 
of the ventral margin. The type species of Dacryomya, Nuculana lacryma (J. de C. 
Sowerby) (1824a : 119, pi. 476, fig. 3), Bathonian of Europe and Asia, is less gibbose 
and has a more elongate rostrum. In Nuculana gutta (Miinster) (= Nucula muc- 
ronata Goldfuss 1837, pi- I2 5» n g s - 9&-d, non Sowerby), also known as N. diana 
(d'Orbigny), Toarcian and Aalenian of Europe, the postero-dorsal profile is less 
strongly concave and the rostrum less well defined. 



FROM TANGANYIKA AND KENYA 27 

Nuculana (Dacryomya) dodsoni sp. nov. 
PL 1, figs. 2a, b, c 

Specific name. After Mr. R. G. Dodson, of the Geological Survey of Kenya. 

Diagnosis. Of medium size (length of largest specimens 15 mm.), pyriform, with 
the height slightly exceeding half the length ; inflation moderate ; with strongly 
opisthogyrous umbones placed just anterior to mid-length and a slightly upcurved 
posterior rostrum, the extemity of which is truncated and situated below mid-height. 
Postero-dorsal outline strongly concave ; antero-dorsal outline and anterior and 
ventral margins forming an uninterrupted, parabolic curve, the ventral margin 
convex as far as its posterior extremity. External features of shell unknown. 

Holotype and paratypes. Numerous internal moulds exposed, together with 
moulds of a species of Nucula, on a bedding plane of hard brownish limestone. The 
holotype (no. L. 98280) is the specimen represented in PL 1, fig. 2c. 

Locality and horizon. Hagardulun, 25 miles N.E. of Tarbaj, N.E. Kenya ; 
Bathonian-Callovian, Bur Mayo Limestones. 

Remarks. Nuculana decorata (Douville) (1916 : 61, pi. 5, figs. 56-62), Bathonian 
of Sinai, is very similar to this species, but differs in its broader umbonal region. 
The widespread Bathonian species N. lacryma (J. de C. Sowerby) has a more sharply 
pointed and upcurved rostrum and a more strongly convex ventral margin. The 
Callovian species N. moreana (d'Orbigny) (types figured by Cottreau 1925 : 12, pi. 
38, figs. 4, 5), which is doubtfully distinct from N. lacryma, differs in the same manner. 
The Toarcian-Aalenian species N. rostralis (Lamarck) (type figured by Favre 1914, 
pi. 35, figs. 242a, b) has less prominent umbones and a less strongly concave postero- 
dorsal margin. The Oxfordian species N. acuta (de Loriol) (1899 : 164, pi. 10, figs. 
29-32, ex Merian, MS.) has a narrower posterior extremity, a less concave postero- 
dorsal margin, and a distinct sinus at the posterior end of the ventral margin. N. 
matheyi (Rollier) (1912 : 62, pi. 6, fig. 5), another Oxfordian species, has a less 
prominent umbo. 

Subgenus RYDERIA Wilton 1830 

Nuculana (Ryderia) kenyana sp. nov. 
PL 1, figs. 6a, b, c 

Diagnosis. Of medium size (height up to 9 mm., original length possibly three 
times that amount), very compressed, inequilateral, with an evidently long posterior 
rostrum, the extremity of which, however, is broken away in all the specimens. 
Umbones very obtuse, only feebly opisthogyrous, level with the almost straight, sub- 
horizontal antero-dorsal margin. Anterior margin flattened, forming an obtuse 
angle with antero-dorsal margin ; ventral margin almost straight except for a slight 
sinus at beginning of posterior rostrum. Postero-dorsal outline feebly concave ; 
escutcheon narrow, shallow, bordered by umbonal ridges which are well defined only 



28 JURASSIC BIVALVIA AND GASTROPODA 

near the umbones. Surface apparently bearing concentric threads and rugae (the 
former, however, almost obliterated by erosion in the available specimens). 

Holotype and paratypes. Nos. LL.35001 and LL.35002-04 respectively, four 
specimens in all. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This species differs from the European Upper Liassic species Nuculana 
rostralis (Lamarck) (synonym, N. claviformis (J. de C. Sowerby) (1824a : 119, pi. 476, 
fig. 2)) in its more compressed form, its almost horizontal and more extended antero- 
dorsal margin, and its flatter anterior margin. It is more closely comparable to N. 
(Ryderia) doris (d'Orbigny) ( = Nucula compianata Goldfuss 1837, pi. 125, figs, na-c, 
non Phillips) and N. (R.) graphica (Tate) (1870 : 407, pi. 26, fig. 12), both of Liassic 
(Pliensbachian) age, but it differs from these species in its more quadrate anterior 
end and its flatter ventral margin. 

Lemoine (1906 : 112) recorded N . doris from a locality south of Kola, Madagascar, 
where it was associated with a Posidonia identified as P. alpina Gras, and where he 
thought the beds might be Aalenian in age. As the specimens from that locality 
have not been figured, it is impossible to say if they belong to the species now 
described. 

Subgenus PRAESACCELLA Cox 1940 

Nuculana (Praesaccella) camelorum sp. nov. 
PI. 2, figs, iofl, b 
i960. Nuculana (Praesaccella) cf. juriana Cox ; Thompson & Dodson : 23 (listed). 

Diagnosis. Of medium size for the genus (length of largest specimen 9-3 mm.), 
pyriform, with height about one-half of length ; inflation rather weak ; with 
obtusely subangular umbones placed at about anterior third of length and an acutely 
pointed posterior extremity which is almost at mid-height. Postero-dorsal outline 
straight or slightly concave ; escutcheon narrow, not well seen in available specimens. 
Antero-dorsal outline and anterior and ventral margins forming an uninterrupted 
curve ; ventral margin in some specimens convex as far as its extremity, in others 
with a small sinus at its posterior end. Ornament of very fine, regular concentric 
threads. 

Holotype and paratypes. Numerous specimens exposed on a bedding-plane 
of hard brownish limestone. The holotype (no. L. 98280) is the one represented in 
the bottom right-hand corner of PI. 2. fig. 106. 

Locality and horizon. Camel track about 5 miles S. of Singu and 9 miles E. of 
Tarbaj, N.E. Kenya ; Toarcian or Bajocian, top of Didimtu Beds. 

Remarks. Nuculana (Praesaccella) juriana Cox (1940 : 33, pi. 2, figs. 6-9), from 
the Oxfordian of Cutch, India, is less inequilateral, higher in proportion to its length, 
and ornamented with slightly coarser concentric threads. No more closely com- 
parable species can be cited. 



FROM TANGANYIKA AND KENYA 29 

Genus ROLLIERIA Cossmann 1920 

Rollieria aequilatera (Koch & Dunker) 
PI. i, figs. 5«, b, c 

1837. Tellina aequilatera Koch & Dunker : 30, pi. 2, fig. 9. 
1850a. Leda delila d'Orbigny : 253. 

1869. Leda aequilatera (Dunker & Koch) ; Brauns : 267. 
1908a. Leda delila d'Orbigny ; Thevenin : 57, pi. 14, figs. 28-30. 

Material. One specimen (no. LL. 35005). 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. Rollieria includes the small, ovate, equilateral, compressed nuculanids 
which range throughout the Jurassic and are difficult to separate into species. 
Elsewhere (Cox 1936 : 464) I have applied the name Nuculana {Rollieria) bronni 
(Andler) to a species ranging from Lower to Middle Lias. I refer the present Upper 
Liassic specimen to R. aequilatera (Koch & Dunker), a species based on an Inferior 
Oolite specimen, and I place Leda delila d'Orbigny, based on a Toarcian specimen, 
in synonymy, as was suggested by Brauns (1869). The range of R. aequilatera 
extends, according to that author, to the ornatus-beds (Callovian). The specimen 
from the Yorkshire Upper Lias figured as Leda aequilatera by Tate (1876, pi. 11, 
fig. 10) was wrongly identified and not even a Rollieria. The present specimen from 
Kenya, which is 9 mm. long, has the outline of a typical Rollieria, and is referred to 
the genus with confidence although it shows no hinge-teeth. 

Superfamily ARCACEA 

Family PARALLELODONTIDAE Dall 1898 

Genus PARALLELODON Meek & Worthen 1866 

Parallelodon pindiroensis sp. nov. 



PI. 1, figs, ya, b, 8a, b 



Diagnosis. Of medium size (length of holotype c. 33 mm.), subrectangular to 
trapeziform in shape, variable also in ratio of length to height. Umbones rising very 
little above hinge-margin, broadly rounded or with a slight median depression ; 
beaks at anterior third or quarter of length of shell. Hinge-margin extended 
posteriorly as a short, acutely pointed wing, the tip of which lies almost exactly 
above posterior end of body of shell. Posterior area much compressed, not sepa- 
rated from the flank by a distinct carina, but bordered near the umbo by a broadly 
rounded ridge which soon dies out. A median depression of the flank and a corres- 
ponding broad sinus of the ventral margin are variably developed. Cardinal area 
rather narrow. Posterior area bearing very weak radial riblets, the remainder of the 
surface radial threads which are obscure except on the antero-dorsal region ; growth- 
rugae present at irregular intervals. 



30 JURASSIC BIVALVIA AND GASTROPODA 

Holotype and paratypes. Nos. LL.35086 and LL.35087-88 respectively, three 
specimens in all, ex B.P. Coll. 

Locality and horizon. Lihimaliao creek, at a point near Mbaru creek, Mand- 
awa area, Tanganyika ; Bajocian (?), Pindiro Shales. 

Remarks. The variability is illustrated by the following measurements of the 
holotype and of the better preserved paratype. Holotype : length 33-3 mm., height 
17-0 mm., inflation 12-5 mm. Paratype : length 32-5 mm., height 18-2 mm., 
inflation 13-5 mm. 

Parallelodon elongatus (J. de C. Sowerby) (1824a: 67, pi. 447, fig. 1), a widespread 
European Bajocian species, and P. buckmani (Richardson) (1843 : 504, text-fig. 243), 
Lower Lias of England, are more elongate, less compressed postero-dorsally, and 
without the wing-like extension of the hinge-margin. 

Genus GRAMMATODON Meek & Hayden i860 
Grammatodon kenyanus sp. nov. 
PI. 2, figs. la, b, c, 2a, b 

Diagnosis. Small (length of largest specimen 15 mm.), rectangularly ovate, not 
much elongated (height two-thirds of length), well inflated, most so just posterior to 
middle of shell. Umbones at about anterior two-fifths of length, broadly rounded 
except for a slight median depression, projecting slightly above hinge-margin. 
Posterior margin nearly straight, meeting hinge-margin in a fairly well-marked, 
slightly obtuse angle. Posterior area somewhat compressed dorsally, not separated 
from flank by a carina. Ornament consisting of concentric ribs which become 
irregular in later growth-stages ; radial threads, traces of which are seen in places, 
may have been present on the whole surface, but, if so, have been largely removed 
by erosion in the available specimens. 

Holotype and paratypes. Nos. LL. 35006 and LL. 35007-09 respectively, four 
specimens in all. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. As the hinge-structure cannot be observed, it is not certain that this 
species belongs to Grammatodon rather than to Cucullaea, but it is included in the 
former genus on account of its small size. It is less elongate but has a relatively 
longer hinge-margin than G. muensterii (Zieten) (1833 : 75, pi. 56, figs, ya-c), Middle 
[?-Upper] Lias of Europe, and also differs in the presence of the concentric ribs. 

Grammatodon sublaevigatus (Zieten) 
PI. 2, fig. 7 

1S33. Cucullaea sublaevigata Hartmann [MS.] ; Zieten : 75, pi. 56, figs. $a-c. 

1837. Area cucullata Miinster [MS.] ; Goldfuss : 148, pi. 123, figs. ya-c. 

1837. Area concinna (Phillips) ; Goldfuss : 148, pi. 123, figs. 6a, b (non Cucullaea concinna 

Phillips). 
[952. Grammatodon cf. bathonicus Cox & Arkell ; A vers : **■ 



FROM TANGANYIKA AND KENYA 31 

Material. Two internal moulds (nos. L. 83863, L. 83869) preserved in pink lime- 
stone with numerous other bivalve remains. 

Locality and horizon, i mile N. of Asaharbito, N.E. Kenya ; Bathonian 
[? or Callovian], Asaharbito Beds. 

Remarks. Largely owing to differences in the state of preservation of material 
from different formations, specific discrimination among the Bajocian, Bathonian 
and Callovian forms of the group of Grammatodon concinnus (Phillips), itself a species 
of Oxfordian age, presents some difficulty. Zieten's Cucullaea sublaevigata was the 
first species of this group to be founded on specimens from one of these stages (Bajo- 
cian), and, since his figure agrees quite well with the specimens now recorded, parti- 
cularly the more elongate one, his specific name is here applied to them. Later 
names which seem to be synonymous with it include Cucullaea inflata Roemer (1836 : 
105, pi. 6, fig. 22), Area cucullata Goldfuss 1837, Area subconcinna d'Orbigny 1850 
(= Area concinna Goldfuss, 1837, pi. 123, figs. 6a, b, non Phillips sp.), Grammatodon 
goldfussi Arkell 1930 (based on the same figures of Goldfuss), and possibly G. bathoni- 
cus Cox & Arkell 1948 (= Cucullaea concinna Morris & Lycett 1853, pi. 5, fig. 7, non 
Phillips sp.). 

Subgenus INDOGRAMMATODON Cox 1937 

Grammatodon (Indogrammatodon) virgatus (J. de C. Sowerby) 

PL 2, figs. 4, 5 

18406. Cucullaea virgata J. de C. Sowerby, pi. 22, figs. 1, 2 and explanation. 

1900. Cucullaea lasti Midler : 533, pi. 17, figs. 1, 2. 

1940. Grammatodon (Indogrammatodon) virgatus (J. de C. Sow.) ; Cox : 47, pi, 2, figs. 22-30. 

Material. Several specimens, ex B.P. Coll., those presented to the Museum 
bearing the numbers LL. 35089-90. 

Localities and horizons. |- mile N.W. of bridge over Mkulumuzi river, 2 miles 
W. of Tanga, Tanganyika ; Callovian. Lonji creek, W. of Mandawa, Tanganyika ; 
Callovian(P). Along Lihimaliao stream at a point about f mile E. of Njenja, Tangan- 
yika ; Upper Oxfordian (?). 

Remarks. These specimens agree, on the one hand, with " Cucullaea " lasti, 
originally described from Callovian beds at a locality west of the Mahokondo creek, 
N.W. of Kiswere, Tanganyika, and, on the other hand, with specimens of " Cucul- 
laea " virgata from its type-area, Cutch. The number of ribs on the left valve, 
omitting a few weak ones, some intercalated between the main ones, others occupying 
the posterior area, varies from about 17-24 ; the number on the right valve is con- 
siderably larger and at the same time even more variable. 

Grammatodon (Indogrammatodon) stockleyi Cox 

PL 2, fig. 9 

1937a. G. (I.) stockleyi Cox : 197, 200, pi. 16, fig. 1. 
i960. G. (I.) stockleyi Cox ; Joubert, pi. 6, figs. 8a, b. 



32 JURASSIC BIVALVIA AND GASTROPODA 

Material. The holotype (no. L. 54109), described previously, and several para- 
types and later collected specimens. 

Localities and horizons. S. of Tarawanda, 11 miles S.E. of Lugoba, Tangan- 
yika ; Callovian. Scarp face, eastern margin of Makoko plain, Bagamoyo hinterland, 
Tanganyika ; Oxfordian. Wilderri hill, n miles S.S.W. of Rahmu, N.E. Kenya ; 
Upper Oxfordian, Seir Limestones. 

Remarks. The largest specimens are 90 mm. long. Among representatives of 
Indogrammatodon this species is exceeded in size only by G. (I.) iddurghurensis Cox, 
from the Argovian of India. The number of main ribs on the left valve may be as 
few as 11, but is usually about 15. 

Grammatodon (Indogrammatodon) irritans (Hennig) 

PI. 2, fig. 3 

19146. Cucullaea irritans Hennig : 175, pi. 14, fig. 6. 

1933. Cucullaea irritans Hennig ; Dietrich : 26, pi. 2, figs. 23-32. 

i960. Grammatodon {Indogrammatodon) irritans (Hennig) ; Joubert, pi. 6, fig. 7. 

Material. Numerous specimens. 

Localities and horizons. Tendaguru neighbourhood (1 mile N. W. of Tendaguru 
hill, Kindope, and Kipande path), Tanganyika ; Upper Kimmeridgian, Nerinella 
and " Trigonia smeei " Beds. Kinjele, 5 miles W. of Mtapaia, N. of Tendaguru, 
Tanganyika ; Upper Kimmeridgian, Indogrammatodon Bed. Dusse, i| miles S.E. 
of Rahmu, N.E. Kenya ; Upper Oxfordian, Seir Limestones. Hereri river crossing, 
3 miles S. of Melka Kunha, N.E. Kenya ; Kimmeridgian, Hereri Shales. 

Remarks. Compared with G. (I.) virgatus, this species is smaller, less elongate, 
more strongly inflated, and more sharply carinate posteriorly, with a more pronounced- 
ly concave posterior area. The largest specimens examined are about 35 mm. long. 
The number of ribs anterior to the carina on the left valve is usually about 15, but 
there may be one or two fewer. In some specimens the number on the right valve 
is about the same, but in others it is considerably greater. In some right valves the 
ribbing is only feebly developed near the posterior carina. 

Grammatodon (Indogrammatodon) matapwaensis sp. nov. 

PI. 2, figs. 6a, b 

Diagnosis. Small (length of larger specimen 17 mm.), rectangularly ovate, sub- 
equilateral, not much elongated, well inflated, most so anteriorly to mid-length. 
Umbo almost median, projecting to a moderate extent above hinge-margin. Poster- 
ior area feebly concave, the boundary between it and the flank rounded off, not form- 
ing a distinct carina. Flank and area ornamented with well separated, unevenly 
spaced radial threads, with densely and regularly arranged concentric threads over- 
riding them and occupying their intervals ; the radial threads are slightly the more 
closely arranged on the right valve, where one or (rarely) two weaker intercalary 



FROM TANGANYIKA AND KENYA 33 

threads may occupy the main intervals ; the total number anterior to the carina on 
the left valve is uncertain, but must have exceeded 20. 

Holotype and paratype. Nos. LL.35091, LL.35092 respectively, both ex B.P. 
Coll. 

Locality and horizon. N. of Matapwa, Pindiro area, Tanganyika ; Upper 
Kimmeridgian. 

Remarks. This species is more nearly equilateral than G. (I.) irritans and has a 
blunter boundary between its flank and posterior area and more numerous ribs. 
The delicate concentric threads which form part of its ornament have not been 
observed in G. (I.) irritans. 



Genus APOLINTER Casey 1961 

Apolinter kindopeensis sp. nov. 
PI. 3, figs. 3a, b, 4a, b 

Diagnosis. Small, with the length (16 mm. in the larger specimen, the holotype) 
slightly less than twice the height ; convexity moderate. Ventral margin evenly 
convex, its general direction diverging from the hinge-margin in a posterior direction, 
so that the shell is highest near its posterior end. Umbo broadly rounded, placed at 
about anterior third of length of shell, protruding slightly above the hinge-margin. 
A well-defined umbonal ridge, curved with an upward-facing convexity, runs to the 
postero-ventral corner of the shell and delimits a narrow, concave posterior area. 
Hinge-margin about three-quarters of length of shell ; postero-dorsal angle obtuse. 
It is evident that the ligamental area, although not seen in available specimens, was 
narrow, and that the umbones of the two valves were very little separated. Orna- 
ment of regular, close-spaced, depressed concentric ribs. 

Holotype and paratype. Nos. L. 56243, L. 56244 respectively. 

Locality and horizon. Kindope, 2 miles N.N.W. of Tendaguru, Tanganyika. 
Upper Kimmeridgian, Nerinella Bed. 

Remarks. The specimens are casts preserved in sandstone and retain traces of 
the concentric ornament of the original shell, although not of any radial ornament 
that may have been present at its extremities. There is no evidence as to the arrange- 
ment of the hinge-teeth. The species is referred to Apolinter on account of its very 
close resemblance to the type-species of that genus, Area aptiensis Pictet & Campiche, 
as figured by Woods (1899 : 35, pi. 6, figs. 8, 9). The dentition of Apolinter, figured 
by Casey (1961 : 589, fig. 11a) is of the general type characteristic of the genera 
Parallelodon and Grammatodon. 

No very closely comparable described Jurassic species can be cited. In the 
Lower Volgian species " Cucullaea " schourovskii Rouillier, referred to Macrodon by 



34 JURASSIC BIVALVIA AND GASTROPODA 

Borissiak (1905 : 12, pi. 2, figs. 10-14), the ventral margin is usually parallel with 
the hinge-margin, although in Borissiak's " var. a " (fig. 13) there is a slight tendency 
for them to diverge posteriorly. In the Callovian species " Cucullaea " rouilleri 
Trautschold, referred to Macrodon by Borissiak (1905 : 8, pi. 2, figs. 1-4) and to 
Beushausenia by Cossmann (1923 : 15, pi. 6, figs. 14-17), the two margins are as 
strongly divergent as in the new species, but the shell is more inequilateral and dis- 
tinctly irregular in form, some specimens having a broad, shallow sinus of the ventral 
margin. 

Family CUCULLAEIDAE Stewart 1930 

Genus CUCULLAEA Lamarck 1801 

Cucullaea kipandeensis sp. nov. 
PI. 3, figs, la, b 

Diagnosis. Of medium size, with the length (48-5 mm. in the holotype) well 
exceeding the height (38 mm.), strongly inflated, most so anterior to mid-length, 
tapering slightly in a posterior direction, with posterior half of ventral margin 
flattened or very feebly concave. Umbonal region very broadly rounded and 
prominent, the summit just anterior to mid-length. Posterior carina well marked 
although rounded off, with a slight sigmoidal curvature, and delimiting a concave 
posterior area which is just visible in the side view of the shell. Anterior two- 
thirds of flank ornamented with strong, narrow, widely and irregularly spaced radial 
ribs, which on its posterior third are replaced by closely spaced, weak riblets crossed 
by concentric threads ; posterior area with a few faint radial threads. A few coarse 
concentric corrugations mark the later growth-stages of the shell. 

Holotype and paratypes. Holotype, no. L.53146. There are two paratypes, 
both ill-preserved. 

Locality and horizon. Kipande, W. of Tendaguru, Tanganyika ; Upper 
Kimmeridgian, Nerinella Bed. 

Remarks. The posterior part of the hinge is not clearly exposed and it is un- 
certain if the species is correctly included in Cucullaea. It is not so elongate as 
typical species of Parallelodon, while its better defined posterior area and its poster- 
ior taper distinguish it from Indogrammatodon. This species recalls a Toarcian shell 
figured by Cossmann (1915a : 16, pi. 6, figs. 6-8) under the name Parallelodon guibali , 
but its radial ornament is stronger than in Cossmann's shell and it is less inequi- 
lateral. There is also a general similarity to Cucullaea elegans Roemer (1836 : 103, 
pi. 6, figs. i6«, b), also from the Upper Lias, and it is to be suspected that Cossmann's 
specimen should have been referred to Roemer's species. Imperfect specimens from 
Tendaguru figured by Dietrich (1933 : 27, pi. 2, figs. 33-35) as a Cucullaea of the 
group of C. contracta (Phillips) may have belonged to the present species, but the 
radial ribs indicated in that author's illustrations are indistinct, perhaps owing to the 
eroded condition of the specimens. 



FROM TANGANYIKA AND KENYA 35 

Family ARCIDAE 
Genus EONAVICULA Arkell 1929 

Eonavicula sp. " A " 

PL 2, figs. 8a, b 

Material. One specimen (no. L. 92046). 

Locality and horizon. Muddo Erri, 12 miles W. of Rahmu, N.E. Kenya ; 
Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Description. This specimen is 31-5 mm. long, well elongated and strongly in- 
equilateral, with the umbo at about the anterior quarter of the length. The sym- 
metrically arched ventral margin is almost flat in the middle ; the growth-lines show 
that it had a shallow median sinus at an earlier stage of growth. The well-marked 
posterior carina has a gentle upward-facing concavity and borders a posterior area on 
which the internal mould has one conspicuous radial sulcus and traces of at least one 
other above it. Although mainly an internal mould, the specimen retains a few 
portions of the original shell on which well-marked growth-rugae are crossed by fine 
radial threads. 

Remarks. This specimen, which has the general appearance of an Eonavicula 
although its hinge-structure is not seen, is more strongly inequilateral than the 
Bathonian species E. minuta (J. de C. Sowerby), the best figure of which, published 
by Morris & Lycett (1853, pi. 5, fig. 17), is misidentified as Area aemula. The 
Oxfordian (Corallian) species E. quadrisulcata (J. de C. Sowerb}') (Arkell, 1929a, pi. 1, 
figs. 3-5) is less elongate and inequilateral, and has four sulci on its posterior area. 
The Kimmeridgian species E.fracta (Goldfuss) (1837 : 141, pi. 121, figs. 10a, b) is as 
elongate as the present specimen but is not quite so strongly inequilateral, while, 
according to Goldfuss's figure, its posterior area is without sulci. The specimen now 
described may thus belong to a new species, but it seems undesirable to assign a name 
to it as it retains so little of its shell. 

Eonavicula sp. " B " 
PL 3, fig. 2 

Material. One specimen (no. LL.11517). 

Locality and horizon. Kindope, N.N.W. of Tendaguru, Tanganyika ; Upper 
Kimmeridgian, Nerinella Bed. 

Description. This specimen, an internal mould, is 22-5 mm. long, well elonga- 
ted, and moderately inequilateral, with the umbo at about the anterior third of the 
length. The whole of the posterior half of the ventral margin forms a broad sinus. 
The well-marked posterior carina has a gentle upward-facing concavity, and above 
it are two radial sulci. 

Remarks. This specimen differs from the equally elongate Eonavicula sp. " A " 
in the more anterior position of its umbo and in the broad sinus of the posterior part 



36 JURASSIC BIVALVIA AND GASTROPODA 

of the ventral margin. It is much more elongate than a specimen from Tendaguru 
recorded by Dietrich (1933 : 26, pi. 2, fig. 36) as Area (Eonavicula) cf. quadrisulcata 
(Sow.). E.fracta (Goldfuss) (1837 : I 4 I « P L I2I > n § s - 10a > fy, from the Kimmerid- 
gian of Germany, is similarly elongate, but the broad sinus of its ventral margin 
occupies a more anterior position. 



Superfamily MYTILACEA 

Family MYTILIDAE Rafinesque 1815 

Genus LITHOPHAGA Roding 1797 

Lithophaga suboblonga Dietrich 

1933. Lithophaga suboblonga Dietrich : 73, pi. 7, figs. 94, 95. 

Material. Numerous crypts preserved in limestone. 

Localities and horizons. Kipande creek, Lilomba creek, Tingutitinguti creek, 
and N.E. of Nguruwe, all near Tendaguru, Tanganyika ; Upper Kimmeridgian, 
" Trigonia smeei " Bed. Kindope, 2 miles N.N.W. of Tendaguru, Tanganyika; 
Upper Kimmeridgian, Nerinella Bed. 

Genus MODIOLUS Lamarck 1799 

Modiolus imbricatus (J. Sowerby) 
PI. 3, figs. 5, 6 

1818a. Modiola imbricata J. Sowerby : 21, pi. 212, figs. 1, 3. 

1935a. Mytilus {Modiolus) imbricatus (J. Sowerby) ; Cox : 162, pi. 16, figs. 3-5. 

Material. About four specimens. 

Localities and horizons. Lihimaliao creek, at a point near Mbaru creek, 
Mandawa area, Tanganyika ; Bajocian (?), Pindiro Shales. Tifo, 14 miles N. of 
Wergudud, and Korkai Hammassa, 19 miles E. of Takabba, both N.E. Kenya ; 
Oxfordian, Golberobe Beds. 

Remarks. Although from two well separated horizons, all the specimens now 
recorded seem indistinguishable from the typical M. imbricatus. The range of this 
species in Europe is generally accepted as from Bajocian to Callovian, and closely 
comparable forms found in the Oxfordian and Kimmeridgian have usually been 
identified as M. aequipiicatus (Strombeck) (M. subaequiplicatus (Roemer)). The 
view that such forms are specifically inseparable from M. imbricatus was adopted by 
me in 1935 when recording specimens from both the Callovian and the Oxfordian of 
British Somaliland, and I am still convinced of its correctness. 



FROM TANGANYIKA AND KENYA 37 

Modiolus anatinus (Smith) 
PI- 3, %• 7 

1817. Modiola anatina Smith : 89. 

1818a. Modiola cuneata J. Sowerby : 19, pi. 211, fig. 1. 

1818a. Modiola gibbosa J. Sowerby : 19, pi. 211, fig. 2. 

1818a. Modiola reniformis J. Sowerby : 20, pi. 211, fig. 3. 

Material. About ten specimens. 

Locality and horizon. Kidugallo Station and i\ miles to the east, Central 
Railway, Tanganyika ; Bajocian, Station Beds. 

Remarks. The type-specimens of the above-cited species described by J. 
Sowerby, which are in the British Museum (Natural History), are all from the Fuller's 
Earth (Bathonian), although Sowerby wrongly stated that those of M. cuneata and 
M. reniformis were from the Inferior Oolite. They all belong to the same species, 
which Smith (1817) had described as M. anatina. In Europe it is wide- 
spread in the Bajocian and Bathonian and has been recorded from the Callovian. 

This species differs from M. irnbricatus in its greater inflation, its shorter form and 
more distinctly cuneiform outline, and shorter and more bulging antero-ventral lobe, 
which is separated from the flank by a furrow which tends to become accentuated 
when specimens, like those now recorded, have been partly flattened by pressure. 



Modiolus bipartitus (J. Sowerby) 
PI- 3, fig- 9 

1818a. Modiola bipartita J. Sowerby : 17, pi. 210, figs. 3, 4. 
1929a. Modiola bipartita J. Sowerby ; Arkell : 55, pi. 2, figs. 1-4. 
1948. Modiolus bipartitus J. Sowerby ; Cox & Arkell : 4. 

Material. Two specimens (nos. L.52087, LL. 35093), the latter ex B.P. Coll. 

Localities and horizons. \ mile N.W. of bridge over Mkulumuzi river, 2 miles 
W. of Tanga, Tanganyika ; Callovian. Tingutitinguti creek, Tendaguru, Tangan- 
yika ; Upper Kimmeridgian, " Trigonia smeei " Bed. 

Remarks. These specimens have a shorter hinge-margin, a less pronounced 
postero-dorsal angle, and a more convex antero-ventral lobe than those referred to 
M. irnbricatus. They are smaller than the holotype of M. bipartitus and the other 
English specimens figured by Arkell, but agree with them in shape. The affinities of 
a specimen from Tendaguru recorded by Dietrich (1933 : 72, pi. 2, fig. 42) as " Modio- 
la sp., Gruppe der M. bipartita " are less certain. The range of the species in England 
is Upper Bathonian (Lower Cornbrash) to Kimmeridgian, but it is rare above the 
Oxfordian. 



38 JURASSIC BIVALVIA AND GASTROPODA 

Modiolus virgulinus (Thurmann & Etallon) 
PI. 3, fig- 8 

1862. Mytilus virgulinus Thurmann & Etallon : 224, pi. 29, fig. 6. 
1875. Mytilus virgulinus Etallon ; de Loriol : 152, pi. 18, figs. 17, 18. 
i960. Modiolus virgulinus (Etallon) ; Joubert, pi. 6, figs. 12a, b. 

Material. One specimen (no. L.92181). 

Locality and horizon. 3 miles N.E. of Melka Dakacha, N.E. Kenya ; Upper 
Kimmeridgian, Dakacha Limestones. 

Remarks. This specimen agrees very closely in shape with de Loriol's fig. 18, 
cited above. It is, however, rather eroded near the dorsal margin and so does not 
show the strong growth-rugae which are confined to this region in typical specimens 
of the species. M. virgulinus, as its name suggests, occurs in France in the " Virgu- 
lian " stage of the Kimmeridgian. 



Subgenus INOPERNA Conrad 1875 

Modiolus (Inoperna) sowerbianus (d'Orbigny) 
PI. 3, figs. 10, 11 

1819a. Modiola plicata J. Sowerby : 87, pi. 248, fig. 1 (non Mytilus plicatus Gmelin 1791). 

1850a. Mitylus [sic] sowerbianus d'Orbigny : 282. 

1910. Modiola plicata Sow. ; Dacque : 30, pi. 5, fig. 10. 

1940. Modiolus (Inoperna) plicatus J. Sowerby ; Cox : 71, pi. 5, figs. 13, 14. 

Material. Two fragments from the Toarcian ; several specimens from higher 
beds. 

Localities and horizons. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. Korkai Hammassa, 19 miles E. of Takabba, 
N.E. Kenya, and Tifo, 14 miles N. of Wergudud, N.E. Kenya ; Oxfordian, Golberobe 
Beds. 

Remarks. In this species each of the strong oblique ribs which meet the dorsal 
margin of the shell splits up half-way to the diagonal carina into from three to 
several weak ribs, or is replaced by them without distinctly splitting up. This 
feature of the ribbing is observable in the Toarcian specimens now recorded and in 
the best preserved one from higher beds. 

D'Orbigny's replacement name is here adopted for the species in consequence of 
the Article 59(b) of the International Code, whereby secondary homonymy pro- 
duced prior to 1961 (in this case by d'Orbigny's transference of Sowerby's species to 
Mytilus) requires a permanent change of the specific name. 



FROM TANGANYIKA AND KENYA 39 

Modiolus (Inoperna) perplicatus (Etallon) 
PI- 3. %• 14 

1862. Mytilus perplicatus Etallon, in Thurmann & Etallon : 223, pi. 29, fig. 8. 

1913. Modiola (Pharomytilus) perplicata (Etallon) ; Dietrich : 73. 

19146. Modiola perplicata (Etallon) ; Hennig : 176, pi. 14, fig. 4. 

i960. Modiolus (Inoperna) perplicatus (Etallon) ; Joubert, pi. 6, figs. 13a, b. 

Material. Six specimens. 

Localities and horizons. 3 miles N.E. of Melka Dakacha, N.E. Kenya ; 
Upper Kimmeridgian, Dakacha Limestones. Tendaguru, Tanganyika ; Upper 
Kimmeridgian. Kinjele, 5 miles W. of Mtapaia, N. of Tendaguru, Tanganyika ; 
Upper Kimmeridgian, Indogrammatodon Bed. 

Remarks. This species differs from M. (I.) sowerbianus in that each of the oblique 
ribs meeting the dorsal margin bifurcates half-way to the diagonal carina and is thus 
replaced by exactly two weaker ribs. In Europe this form occurs only in the 
Kimmeridgian. 

Genus MUSCULUS Roding 1797 

Musculus kindopeensis sp. nov. 

PI. 4, figs. la, b 

Diagnosis. Small (length of holotype 9-3 mm.), moderately elongate, with the 
length, measured parallel to the hinge-margin, rather less than twice the height, not 
greatly oblique, ornamented, as in typical Musculus, with radial threads which are 
absent from the concave area separating the antero-ventral lobe from the most 
inflated part of the shell, which runs diagonally from the beak to the postero-ventral 
corner. The threads of the posterior series number about 36 where they meet the 
margin; those of the anterior series about 12. 

Holotype and paratypes. Holotype, no. LL.11331. Six paratypes, nos. 
L.56234, LL. 11328-30, LL.11332, LL.11516. 

Locality and horizon. Scarp at Kindope, 2 miles N.N.W. of Tendaguru, 
Tanganyika ; Upper Kimmeridgian, Nerinella Bed. 

Remarks. This form is less elongate and smaller than the European Kimmerid- 
gian-Portlandian species M. autissiodorensis (Cotteau) (de Loriol 1868 : 625, pi. 12, 
fig. 8 ; 1875 : 152, pi. 18, fig. 14). 

Genus MYTILUS Linnaeus 1758 

Subgenus FALCIMYTILUS Cox 1937 

Mytilus (Falcimytilus) tifoensis sp. nov. 

PI. 3, figs. 12, 13 

1957. Lyceltia dalpiazi Venzo ; Saggerson & Miller : 14. 

Diagnosis. Of medium size (diagonal measurement from beak to postero- 
ventral corner 39 mm. in the holotype), markedly falciform, oblique (the diagonal 



4 o JURASSIC BIVALVIA AND GASTROPODA 

forming an angle of about 45 ° with the hinge-margin), variable in breadth, moderate- 
ly inflated ; dorsal margin not much elongated, meeting the convex posterior margin 
in a broad curve. A very sharp ridge, strongly curved and forming almost a quad- 
rant, runs from the beak to the ventral extremity and separates the flank from a 
narrow antero-ventral region which slopes steeply to the margin and protrudes 
beyond the ridge, so as to be visible in the side-view of the shell only near the beak. 
Surface ornament unknown, the specimens being internal moulds. 

Holotype and paratypes. Holotype, no L.93615. Three paratypes, nos. 
L.93581, L.93616-17. 

Localities and horizon. Tifo, 14 miles N. of Wergudud, and Ogar Wein hills, 
17 miles N.W. of Wergudud, N.E. Kenya ; Oxfordian, Golberobe Beds. 

Remarks. The specimens upon which this species is founded were originally 
recorded (Saggerson & Miller 1957 : 14) as Lycettia dalpiazi Venzo. On careful 
examination, however, they prove to belong to a species of Falcimytilus in which the 
diagonal ridge is unusually sharp, as they differ from Lycettia in the distinct protru- 
sion of the anterior margin beyond the ridge. Mytilus (Falcimytilus) suprajurensis 
Cox (1925 : 142, pi. 1, fig. 9 ; pi. 3, fig. 2 ; 1937c : 344, pi. 17, figs. 1-3), from the 
Kimmeridgian and Portlandian of England, is a closely related but rather larger 
species. 

Mytilus (Falcimytilus) jurensis Roemer 

1836. Mytilus jurensis [ex Merian MS.] Roemer : 89, pi. 4, fig. 10. 
1935a. Mytilus jurensis Roemer ; Cox : 161, pi. 15, figs. 15-17. 

Material. Six specimens. 

Localities and horizons. Romicho, 25 miles S.W. of El Wak, N.E. Kenya ; 
beds just underlying Golberobe Beds (Oxfordian). i\ miles S.W. of Rahmu, N.E. 
Kenya ; Oxfordian, Rahmu Shales. Dusse, 1^ miles S.E. of Rahmu, N.E. Kenya ; 
Upper Oxfordian, Seir Limestones. Hereri river crossing, 3 miles S. of Melka 
Kunha, N.E. Kenya ; Kimmeridgian, Hereri Shales. 

Remarks. Like those from Somaliland figured in the work cited (Cox 1935a), 
these specimens vary considerably in obliquity and in the development of an antero- 
ventral bulge, which gives some of them a modioliform outline. 

Mytilus (Falcimytilus) dietrichi sp. nov. 
PL 3, figs. 15, 16 

19146. Mytilus cf. galliennei d'Orbigny ; Hennig : 157, pi. 14, figs. 3a, b. 
1933. Mytilus sp. ; Dietrich : 72. 

Diagnosis. Of medium size (diagonal measurement from beak to postero-ventral 
corner 33 mm. in holotype), oblique (the diagonal forming an angle of about 45 ° 
with the hinge-margin), variable in breadth, moderately inflated ; dorsal margin not 
much elongated, meeting the convex posterior margin in a broad curve. A blunt 



FROM TANGANYIKA AND KENYA 41 

and scarcely curved ridge runs from the beak to the ventral margin and separates the 
flank from a narrow antero-ventral region, the margin of which presents only a slight 
concavity below the beak and does not project anteriorly to it. Surface unornamen- 
ted. 

Holotype and paratypes. Holotype, no. L.52187 ; numerous paratypes. 

Localities and horizons. Dirahara, 24 miles E.N.E. of Aus Mandula, N.E. 
Kenya, and Tifo, 14 miles N. of Wergudud, N.E. Kenya ; Oxfordian, Golberobe 
Beds. Tendaguru neighbourhood (Kindope valley, Tingutitinguti creek, Lilomba 
creek), and Kinjele, 5 miles W. of Mtapaia, N. of Tendaguru, Tanganyika ; all 
Upper Kimmeridgian, " Trigonia smeei " Bed. 

Remarks. Mytilus galliennei d'Orbigny, the Cenomanian species from France 
to which this form was originally compared by Hennig, has a less marked diagonal 
ridge, lacks any convexity of the anterior margin below the beak, and has weak 
transverse striations on its antero-ventral region. 

Genus BRACHIDONTES Swainson 1840 

Subgenus ARCOMYTILUS Agassiz 1842 

Brachidontes (Arcomytilus) asper (J. Sowerby) 
PI. 4, figs. 2a, b 

1818a. Modiola aspera J. Sowerby : 22, pi. 212, fig. 4. 

1948. Brachidontes (Acromytilus) asper (J. Sowerby) ; Cox & Arkell : 5. 

i960. Brachidontes (Arcomytilus) asper (J. Sowerby) ; Joubert, pi. 6, figs, ioa-c. 

Material. Two specimens (nos. L. 92067, L. 92177). 

Localities and horizons. 2 miles W. of Melka Biini, N.E. Kenya ; Bathonian, 
Murri Limestones. Kulong, 2 miles S.W. of Muddo Erri, N.E. Kenya ; Callovian 
[?-Lower Oxfordian], Muddo Erri Limestones. 

Remarks. The specimens now recorded are typical examples of this species, 
which in England appears to be restricted to the Bathonian, but is known from the 
Callovian of various other areas. 

Brachidontes (Arcomytilus) laitmairensis (de Loriol) 

PI. 4. %• 3 

1883. Mytilus laitmairensis de Loriol : 57, pi. 8, figs. 6-12. 

1935a. Mytilus (Arcomytilus) laitmairensis de Loriol ; Cox : 164, pi. 15, figs. 13, 14. 

i960. Mytilus (Arcomytilus) sp. ; Joubert, pi. 6, fig. 9. 

Material. Four specimens. 

Localities and horizons. Kulong, 2 miles S.W. of Muddo Erri, N.E. Kenya ; 
Callovian [?-Lower Oxfordian], Muddo Erri Limestones. Tifo, 14 miles N. of 
Wergudud, N.E. Kenya ; Oxfordian, Golberobe Beds. N. of Matapwa, Pindiro 
area, Tanganyika ; Upper Kimmeridgian. 



42 JURASSIC BIVALVIA AND GASTROPODA 

Remarks. The differences between this species and B. {A.) subpectinatus (d'Or- 
bignv) { = pectinatus (J. Sowerby)) were discussed by me in the work cited above. 
The specimens now recorded, including those from the Kimmeridgian, agree with 
B. (A.) laitmairensis in their rounded postero-ventral margin and in the absence of a 
definite ridge running from the umbo to the posterior end of this margin. This 
species occurs most commonly in the Callovian, but Arkell has recorded its occurrence 
in the English Oxfordian. It has not been recorded previously from the Kimmerid- 
gian. The true B. (A.) subpectinatus has been recorded from Tendaguru by Dietrich 
( I 933 : 7 2 - P 1 - 2 . n g- 47). but is not represented in the collections from that locality 
in the British Museum (Natural History). 

Superfamily PTERIACEA 
Family PTERIIDAE Gray 1847 

Genus PTERIA Scopoli 1777 

Pteria tanganyicensis sp. nov. 

PL 4( fig. 4 

Diagnosis. Large (original length at least 9 cm.), well inflated, obliquely elon- 
gate, with a rather narrow body which has a slight sigmoidal curvature. Anterior 
wing large, acute, not compressed ; posterior wing more compressed and differentia- 
ted from the body than the anterior one, appearing (from its earlier growth lines) to 
have had an acutely pointed tip (it is broken away distally in the holotype). Sur- 
face of shell without radial ornament. 

Holotype. No. LL. 16793, a right valve damaged posteriorly. The only specimen. 

Locality and horizon. Usigiwa river, 6 miles W.S.W. of Kiwangwa, Baga- 
moyo hinterland, Tanganyika ; Upper Oxfordian. 

Remarks. The cardinal area is not seen in the holotype, so that the number of 
ligamental pits cannot be ascertained, but the species is referred to Pteria as its 
general form is more suggestive of that genus than of any representatives of the family 
Bakevelliidae. In size and shape it much resembles Avicula struckmanni de Loriol 
(1875 : 164, pi. 20, fig. 1), from the Kimmeridgian of France, but it differs in the 
much larger size of its anterior auricle. No comparable form has been recorded 
previously from East Africa. 

Family BAKEVELLIIDAE King 1850 

Genus BAKEVELLIA King 1848 

Bakevellia iraonensis (Newton) 

[80,5, Gervillia iraonensis Newton : So, pi. 2, figs. 8, 9. 

Material. Four specimens (nos. LL. 7224-27). 

Locality and horizon. Quarries N.N.E. of Ngerengere, Central Railway, 
Tanganyika ; Bajocian (?). 



FROM TANGANYIKA AND KENYA 43 

Remarks. Although ill-preserved, these specimens can be seen to have the strong 
inflation and the general outline of Newton's species, the holotype of which, from 
the Bathonian of Madagascar, is in the British Museum (Natural History). Hennig 
(1914a : 65 ; 1924 : 31) has already recorded the presence of a form identified as 
Gervillia aff. iraonensis in Tanganyika. 

Genus GERVILLELLA Waagen 1907 

Gervillella didimtuensis sp. nov. 
PI. 4, figs. 5rt, b, 6 

Diagnosis. Of medium size (measuring up to 50 mm. from anterior end of 
hinge-line to extremity of body), moderately inflated, trapezoidal, oblique ; shell- 
wall very thick. Anterior and ventral margins forming a strongly convex, uninter- 
rupted curve. Body of shell broad, evenly inflated, its level descending gradually 
to the anterior margin and to the posterior wing. Length of hinge-margin about 
four-fifths of that of shell ; posterior wing obtusely angular, apparently not acutely 
pointed at its tip in any stage of growth. Anterior auricle absent ; beak terminal 
in most specimens, but in some the anterior margin projects very slightly beyond it. 
Umbo projecting only very slightly above hinge-margin. Ligamental pits four or 
fewer, extending from beak along about two-thirds of hinge-margin. A rather long, 
oblique, ridge-like tooth, inclined at an angle of about 45 ° with the hinge-margin, 
originates just below the beak ; posterior to it are several small, similarly oblique 
teeth, and near the posterior end of the hinge-margin and diverging only slightly 
from it is a strong, elongate tooth. 

Holotype and paratypes. Nos. LL. 35012 and LL. 35013-16 respectively, five 
specimens in all. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. The absence of an anterior auricle readily distinguishes this species 
from the Bajocian form, Gervillella orientalis, described next. 

Gervillella orientalis (Douville) 
PL 4, figs. ja, b, 8 

1916. Gervillia orientalis Douville : 59, pi. 4, figs. 14-17. 

Material. Several specimens ; ex B.P. Coll. 

Localities and horizon. Lihimaliao creek, at a point near Mbaru creek, 
Mandawa area, Tanganyika ; near site of Mandawa well no. 1, Tanganyika ; depth 
50-52 feet in Mandawa well no. 6, Tanganyika ; all Bajocian (?), Pindiro Shales. 

Description. The shell is of medium size (measuring up to 40 mm. from tip of 
anterior auricle to extremity of body), subequivalve, oblique. The length of the 



44 JURASSIC BIVALVIA AND GASTROPODA 

hinge-margin is about three-fifths of that of the shell. When not broken away, an 
acute anterior auricle extends well beyond the umbo, which projects only slightly 
above the hinge-margin. The anterior and ventral margins form a strongly convex, 
uninterrupted curve. The body of the shell, which varies considerably in breadth 
and obliquity, is evenly and moderately inflated, its level descending gradually to the 
anterior margin and to the posterior wing. The growth-lines show that the posterior 
wing, which is obtusely triangular in general shape, was acutely pointed at its 
extremity in earlier growth-stages. In the material examined some shell fragments 
show traces of hinge-teeth, but the complete dentition is not displayed. 

Remarks. This species was based on several broken specimens from Jebel 
Aroussieh, Sinai. Douville queried their age as Callovian, but a specimen collected 
more recently is from beds which are undoubtedly Bathonian in age. Douville 's 
figures indicate a range of variation similar to that shown by the specimens now 
described, and justify the inclusion of all of these in the same species. The present 
specimens, however, lack the radial sulcus of the body of the shell observable in 
specimens from Sinai. The less expanded specimens of the species rather resemble 
Gervillella ovata (Morris & Lycett), an English Bathonian form, differing mainly in 
the presence of the pointed anterior auricle. G. iraonensis (Newton), Bathonian of 
Madagascar, is a more gibbose shell with a broad sinus of the anterior margin. 

Gervillella siliqua (Eudes-Deslongchamps) 
PL 4, fig. 10 

1824. Gevvillia siliqua Eudes-Deslongchamps : 128, pi. 4. 

1940. Gervillella siliqua (Eudes-Deslongchamps) ; Cox : 112, pi. 7, figs. 12-14. 

Material. One specimen (no. L. 92032). 

Locality and horizon. Tifo, 14 miles N. of Wergudud, N.E. Kenya ; Oxfordian, 
Golberobe Beds. 

Remarks. The specimen now recorded, which is about 45 mm. long, closely 
resembles one from the Oxfordian of Cutch, India, represented in fig. 13 of the work 
cited above. To the synonyms of G. siliqua there given should probably be added 
Gervillia mayeri Moesch (1867 : 308, pi. 5, figs. 10a, b). 

Gervillella aviculoides (J. Sowerby) 

1814a. Perna aviculoides J. Sowerby : 147, pi. 66, figs. 1-4. 

1836. Gervillia telragona Roemer : 85, pi. 4, fig. n. 

1875. Gervillia telragona Roemer ; de Loriol : 165, pi. 19, figs. 3-5. 

1933a. Gervillia aviculoides (J. Sowerby) ; Arkell : 203, pi. 26, figs. 1-5. 

IQ 33- Gervilleia {Gervillella) sp., aviculoides-Gruppe ; Dietrich : 60. 

Material. Several imperfect specimens. 

Localities and horizons, i mile N.W. of Tendaguru hill and scarp at Kindope, 
N.N.W. of Tendaguru, Tanganyika ; Upper Kimmeridgian, Nerinella Bed. Tin- 



FROM TANGANYIKA AND KENYA 45 

gutitinguti creek, Tendaguru ; Upper Kimmeridgian, " Trigonia smeei " Bed. 
Just W. of Mabokweni, 4 miles N.W. of Tanga, Tanganyika ; Kimmeridgian. 

Remarks. De Loriol and other authors have applied Roemer's name Gervillia 
tetragona to a species which occurs in the Kimmeridgian of France and other Euro- 
pean countries. Comparison of French specimens of that age with typical English 
specimens of G. aviculoides , from the Corallian Beds (Oxfordian), has convinced me 
that all belong to the same species. The East African specimens now recorded 
cannot be distinguished from the European species. 

Genus GERVILLIA Defrance 1820 

Gervillia saggersoni sp. nov. 
PI. 4, fig. 11 

Specific name. After Dr. E. P. Saggerson, of the Kenya Geological Survey. 

Diagnosis. Of medium size (length of holotype 62-5 mm.), broadly falciform, 
not greatly oblique, diagonal from umbo forming an angle of about 15 ° with hinge- 
margin. Hinge-margin about one-half of length of shell ; umbo protruding only 
slightly and situated near anterior end of hinge-margin. Anterior and ventral 
margins forming an uninterrupted, strongly convex curve ; posterior extremity 
bluntly rounded. Body of shell, which attains a maximum width of about 17 mm. 
in the holotype, evenly convex ; posterior wing narrow, flattened but not well 
differentiated, with an obtuse outer angle. 

Holotype. No. L. 93622, consisting of internal and external moulds of a left 
valve. A second internal mould (no. L. 93499) is too ill-preserved to rank as a para- 
type. 

Localities and horizon. Korkai Hammassa, 19 miles E. of Takabba, N.E. 
Kenya (type-locality), and Ogar Wein, 17 miles N.W. of Wergudud, N.E. Kenya ; 
Oxfordian, Golberobe Beds. 

Remarks. This form was originally recorded (Saggerson & Miller 1957 : 14) as 
Gervillia cf. monotis Eudes-Deslongchamps, but the true G. monotis, from the Bathon- 
ian of Europe, is a smaller form with a narrower body. The most closely comparable 
species is Gervillia pancici Radovanovic (1900 : 64, pi. 1, figs. 4, 5), from the Lower 
Lias of Yugoslavia, but this appears to have a longer dorsal margin. In view of 
their falciform outline these forms seem better included in Gervillia than in Gervillella. 

Family PINNIDAE 

Genus PINNA Linnaeus 1758 

Pinna buchii Koch & Dunker 

PL 4, fig. 9 

1837. Pinna buchii Koch & Dunker : 33, pi. 2, fig. 18. 

1869. Pinna buchii K. & D. ; Brauns : 230. 

1899. Pinna buchii K. & D. ; Greppin : 99, pi. 13, figs. 5, 6. 



4<> JURASSIC BIVALVIA AND GASTROPODA 

Material. One specimen (no. LL. 35095). 

Locality and horizon. Near site of Mandawa well no. 1, Tanganyika ; Bajo- 
cian (?), Pindiro Shales. 

Remarks. The specimen is a crushed right valve with a sub-median carina on the 
dorsal side of which are about 12 radial riblets ; the ventral side bears well-marked 
growth-folds but is devoid of radial ornament. In having its radial ornament con- 
fined to the dorsal half of the surface the specimen resembles the original figure of the 
species, which represents a specimen from the Inferior Oolite of Holtensen, northern 
Germany ; its riblets, however, are more numerous than in the German specimen. 
In the specimens from the Upper Bajocian of Switzerland figured by Greppin radial 
riblets are present also on the ventral side of the median carina. 

Pinna mitis Phillips 

1829. Pinna mitis Phillips : 137, pi. 5, lig. 7. 

1883. Pinna mitis Phil. ; Lahusen : 27, pi. 2, fig. 12. 

1910. Pinna sp. ; Dacque : 29, pi. 5, fig. 4. 

1924. Pinna mitis Ziet. ; Hennig : 71, pi. 2, fig. 7. 

1934. Pinna mitis Phil. ; Stoll : 19, pi. 2, fig. 9. 

Material. Several specimens. 

Locality and horizon. 6\ miles N.E. of Pande (village on Mkwaja-Mkata road) 
and z\ miles N. of Msangasi stream, N.E. Tanganyika ; Callovian. 

Remarks. The specimens, the largest of which were about 60 mm. long when 
complete, are preserved in a hard sandstone and, when an attempt is made to extract 
them, usually break in such a manner that part of the wall of the shell adheres to 
each counterpart. Sufficient of their ornament can, however, be seen to show that 
it agrees with that of Pinna mitis, already recognized by Hennig (1924) in the Callo- 
vian of Tanganyika. 

Pinna constantini de Loriol 

1875. Pinna constantini de Loriol : 161, pi. 19, fig. 2. 

1897. Pinna constantini de Loriol ; Futterer : 596, pi. 20, figs. 5, 5a. 

1933. Pinna cf. constantini de Loriol ; Dietrich : 60, pi. 8, figs. 131-134. 

Material. Several specimens. 

Localities and horizons. Valley and scarp at Kindope, N.N.W. of Tendaguru, 
Tanganyika ; Upper Kimmeridgian, " Trigonia smeei " and Nerinella Beds. 

Remarks. The specimens from East Africa agree so well with de Loriol's illustra- 
tion of the type specimen from the " Portlandien moyen " of France, that there 
seems no need to qualify the identification. The number of ribs on the dorsal side 
of the median carina of each valve is 5-7, while the number below the carina in- 
creases during growth to 6 or more, the extreme ventral part of the surface bearing 
only growth-folds. 



FROM TANGANYIKA AND KENYA 47 

There is some doubt whether this form should be considered synonymous with 
Pinna ornata d'Orbigny, a French Kimmeridgian species, one of the syntypes of 
which has been figured by Cottreau (1932, pi. 66, fig. 15). The ribs below the median 
carina seem to be weaker in P. ornata, but the difference is not great and only 
relatively small specimens have so far been figured. 

Genus STEGOCONCHA Bohm 1907 
Stegoconcha gmuelleri (Krenkel) 

PL 5, %• 8 

1910. Pinna G. Miilleri Krenkel : 203, pi. 21, fig. 5. 

1933. Stegoconcha solida Bohm var. tendagurensis Dietrich : 61, pi. 9, figs. 138, 139. 

Material. Several specimens. 

Localities and horizons, i mile N.W. of Tendaguru hill, Tanganyika, around 
Kipande, W. of Tendaguru, and Kindope, N.N.W. of Tendaguru ; all Upper 
Kimmeridgian, Nerinella Bed. Dusse, i\ miles S.E. of Rahmu, N.E. Kenya ; 
Upper Oxfordian, Seir Limestones. 

Family MALLEIDAE Gray 1823 

Genus ELIGMUS Eudes-Deslongchamps 1856 

Eligmus rollandi Douville 

PI. 5 , figs. 5, 6 

1907a. Heligmus rollandi Douville : 105, pi. 15, figs. 1-3. 

1929. Heligmus rollandi Douville ; Weir : 23, pi. 1, figs. 24-28. 

1935a. Eligmus rollandi Douville ; Cox : 168, pi. 16, figs. 6-10. 

i960. Eligmus rollandi Douville ; Joubert, pi. 8, fig. 11. 

Material. Several specimens. 

Localities and horizon. Muddo Erri ; Kulong, 2 miles S.W. of Muddo Erri ; 
Muddo river bed 4 miles S.W. of Muddo Erri ; S. of Rahmu-Melka Murri road, 6 miles 
W. of Rahmu ; 14 miles W.S.W. of Rahmu ; all N.E. Kenya : Callovian [?-Lower 
Oxfordian], Muddo Erri Limestones. 

Superfamily PECTINACEA 

Family OXYTOMIDAE Ichikawa 1958 

Genus OXYTOMA Meek 1864 

Oxytoma inequivalvis (J. Sowerby) 

PI- 5. fig- 7 

1819a. Avicula inequivalvis J. Sowerby : 78, pi. 244, figs. 2, 3. 

x 933- Oxytoma inaequivalvis var. hennigi Dietrich : 58, pi. 7, figs. 99-101. 

1940. Oxytoma inequivalve (J. Sowerby) ; Cox : 98, pi. 6, figs. 9-12. 



48 JURASSIC BIVALVIA AND GASTROPODA 

Material. Two specimens. 

Localities and horizons. Chinamba, f mile S. of Amboni quarries, Tanga, 
Tanganyika ; Callovian (?) (ex B.P. Coll.). Kindope valley, N.N. W. of Tendaguru, 
Tanganyika ; Upper Kimmeridgian, Nerinella Bed. 

Genus MELEAGRINELLA Whitfield 1885 

Meleagrinella echinata (Smith) 

1817. Avicula echinata Smith : 67. 

1940. Echinotis echinata (Smith) ; Cox : 92, pi. 6, figs. 2-7. 

1948. Meleagrinella echinata (Smith) ; Cox & Arkell : 7. 

Material. Two specimens. 

Locality and horizon. S. of Tarawanda, 11 miles S.E. of Lugoba, Tanganyika ; 
Callovian. 

Remarks. The specimens now recorded are not well preserved, but the number 
of their ribs is the same as in typical specimens of M. echinata and considerably fewer 
than in the specimens recorded below as M. radiata ; the ribs, moreover, are more 
equal in strength than in M. radiata. Miiller and Hennig have reported M. echinata 
from the " Dogger " of Tanganyika. 

Meleagrinella radiata (Trautschold) 
PI. 5, figs, la, b, 2a, b, 3a, b, 4a, b 

i860. Aucella radiata Trautschold : 343, pi. 6, figs. 7, 8. 

1870. Avicula (Monotis) tenuicostata Greppin : 350, pi. 5, figs, ja, b (non Avicula tenuicostata 
Roemer 184 1). 

1899. Pseudomonotis tenuicostata (Greppin) ; de Loriol : 169, pi. 10, fig. 36. 

1900. Pseudomonotis tenuicostata (Greppin) ; de Loriol : 126, pi. 6, fig. 44. 
1900. Avicula lieberti Miiller : 542, pi. 19, figs. 14-17. 

1910. Avicula tschingira Krenkel : 203, pi. 20, fig. 12. 

1912. Pseudomonotis radiata (Trautschold) ; Sokolov : 108, pi. 2, figs. 11-13. 

1914. Pseudomonotis lorioli Rollier : 312 (for P. tenuicostata de Loriol non Greppin sp.). 

19146. Pseudomonotis tendagurensis Hennig : 182. 

1924. Pseudomonotis epechinata Hennig : 87. 

!933- Pseudomonotis tendagurensis Hennig ; Dietrich : 57, pi. 8, figs. 107-117. 

1938. Pseudomonotis lieberti (Miiller) ; Weir : 45, pi. 3, fig. 5. 

Material. Numerous specimens. 

Localities and horizons. Korkai Hammassa, 19 miles E. of Takabba, Ogar 
Wein, 17 miles N.W. of Wergudud, and Chimpa, all N.E. Kenya ; Oxfordian, 
Golberobe Beds. Plantations N. of Dakatcha village, and also £ mile E. of Merikano, 
both in Malindi district, Coast Province, Kenya ; in loose boulders, respectively of 
hard sandstone and of limestone, of uncertain age. Usigiwa river, 6 miles W.S.W. 
of Kiwangwa, Bagamoyo hinterland, Tanganyika ; Upper Oxfordian. Kiwate- 
Mkange track, 5 miles S.S.E. of Mkange, Bagamoyo hinterland, Tanganyika ; 



FROM TANGANYIKA AND KENYA 49 

Oxfordian or Kimmeridgian. 17 miles S. of Rahmu, N.E. Kenya ; Upper Oxford- 
ian, Seir Limestones. Several localities around Tendaguru, Tanganyika ; Upper 
Kimmeridgian, " Trigonia smeei " and Nerinella Beds. Kinjele, 5 miles W. of 
Mtapaia, N. of Tendaguru, Tanganyika ; Upper Kimmeridgian, Indogrammatodon 
Bed. 

Remarks. Hennig and Dietrich did not adopt Miiller's specific name lieberti, the 
first to be applied to East African specimens of this species, when recording speci- 
mens from Tendaguru, because Miiller's description and figures suggested that he 
was dealing with a form in which the shell was completely smooth. The material 
from this locality now studied, however, includes specimens which appear smooth 
either because their outer shell layer has disappeared or because they are merely 
internal moulds. It thus seems evident that Miiller's types were specimens pre- 
served in one of these ways. Hennig apparently overlooked Krenkel's description 
of Avicula tschingira when founding his species Pseudomonotis tendagurensis. 

In specimens from the Tendaguru district the left valve is ornamented with 
numerous closely arranged, narrow, round-topped riblets of unequal strength, 
increasing by intercalation. Details vary considerably in different shells. On parts 
of the surface in many specimens the riblets alternate in strength or weaker ones 
alternate with pairs of stronger ones. On some specimens the stronger ribs bear 
obscure, evenly spaced, imbricating scales. Right valves are of feeble convexity 
and bear well separated radial riblets. It has seemed important to reach a decision 
as to the identity of the Meleagrinella which is the most abundant species found in 
the Golberobe Beds of northern Kenya, and has been figured by Saggerson & Miller 
(1957 : 19, figs. b-d). I am now convinced that it is not possible to draw any specific 
distinction between this form and the Tendaguru species, as specimens with closely 
similar ornament occur in both areas. Those now illustrated include one (figs. 3a, b) 
with particularly numerous and closely spaced ribs. In the Golberobe specimens 
the right valve is almost smooth, with faint radial ribbing appearing in its later 
growth-stages. The largest of these specimens are about 15 mm. long. 

It is also necessary to discuss whether previous workers have been justified in 
asssuming that the Tendaguru species is distinct from any found in Europe. In M. 
echinata, a European form recorded above from Tanganyika, the left valve is more 
strongly inflated and the ribs are less numerous, stronger, and more uniform in 
strength. In M. braamburiensis (Phillips), which occurs in the European Callovian 
and Oxfordian and has been well figured by Douglas & Arkell (1932 : 163, pi. 12, 
figs. 5, 6), the ornament is very similar to that of the Tendaguru form, but specimens 
commonly attain a length of 25-30 mm., which much exceeds the usual size of the 
latter. The species described by Trautschold as Aucella radiata and discussed in 
1912 by Sokolov (who has included Avicula tenuicostata Greppin in its synonymy) 
appears, however, to be indistinguishable from the East African form, as inspection 
of de Loriol's figures of A . tenuicostata will show. In Europe M. radiata occurs in the 
Lower Oxfordian, so that its recognition in the Golberobe Beds of Kenya is in keep- 
ing with the supposed Oxfordian age of these beds. In view of its occurrence at 



5 o JURASSIC BIVALVIA AND GASTROPODA 

Tendaguru also, it is clear that in East Africa it has a moderately extended geological 
range. 

Family POSIDONIIDAE 

Genus BOSITRA de Gregorio 1886 

Bositra buchii (Roemer) 
PI. 6, fig. 1 



1836 
1851 
1852 
1869 
1896 
1924 
1928 
1930 
1938 
1940 



Posidonia Buchii Roemer : 81, pi. 4, fig. 8. 
Posidonia ornati Quenstedt : 517, pi. 42, fig. 16. 
Posidonomya alpina Gras : 11, 48, pi. 1, fig. 1. 
Posidonomya Buchii (Roemer) ; Brauns : 242. 
Posidonomya Bxichi (Roemer) ; Stremoouchow : 391, pi. 10. 
Posidonomya Buchii (Roemer) ; Hennig : 43. 
Posidonomya alpina Gras ; Guillaume : 228, pi. 10, figs. 4-13. 
Posidonia ornati Quenstedt ; Weir : 83, pi. io, figs. 14-21. 
Posidonia ornati Quenstedt ; Weir : 45, pi. 3, fig. 5. 
Posidonia ornati Quenstedt ; Cox : 103, pi. 7, figs. 10, n. 



Material. Numerous specimens. 

Localities and horizons. Kidugallo Station, Central Railway, Tanganyika ; 
Bajocian, Station Beds. Boreholes 5 miles N. of Kidugallo and at Lugoba, Tangan- 
yika ; Lower Bajocian (Aalenian) (see Arkell, 1956 : 330). About 2.\ miles S.S.W. of 
Tengeni (village on Pangani river), N.E. Tanganyika ; horizon uncertain. Kaya 
Kauma, 8 miles W. of Kilifi, Kenya ; Upper Callovian, Miritini Shales. 

Remarks. Many authorities have recognized that Posidonia buchii was founded 
on an unusually elongate specimen of the species more commonly known as P. ornati 
Quenstedt or as P. alpina (Gras) , and this view is here accepted, although in previous 
works I have used Quenstedt's name for the species. It has an exceptionally long 
geological range, extending from the Toarcian (in Argentina) to the Upper Callovian. 
The recent work of R. P. S. Jefferies has shown that there are good grounds for the 
generic separation of P. buchii and related Jurassic forms from the type-species of 
Posidonia, P. becheri Bronn of the Carboniferous, and the generic name Bositra has 
long been available for them. 

Bositra somaliensis (Cox) 
PI. 6, fig. 2 
1935a. Posidonia somaliensis Cox : 166, pi. 15, figs. 7, 8. 

Material. One specimen (no. L. 51207). 

Locality and horizon. Kindope valley, N.N.W. of Tendaguru, Tanganyika ; 
Upper Kimmeridgian, Nerinella Bed. 

Remarks. This valve of a Bositra, which is about 20-5 mm. long and slightly less 
in height, seems referable to B. somaliensis in view of its size and known geological 
age. B. bononiensis (de Loriol) (1875 : 170, pi. 21, figs. 3-5), from the Kimmeridgian 
of France, is a much smaller form. 



FROM TANGANYIKA AND KENYA 51 

Family AMUSIIDAE Ridewood 1903 

Genus ENTOLIUM Meek 1865 
Entolium corneolum (Young & Bird) 

1828. Pecten corneolus Young & Bird : 234, pi. 9, fig. 5. 

1900. Pecten demissus Phillips ; Muller : 527, pi. 17, fig. 10. 

1924. Pecten demissus Phillips ; Hennig : 14, pi. 2, figs. 1, 2. 

1929. Entolium solidum (Roemer) ; Weir : 23, pi. 1, fig. 33. 

1930a. Entolium demissum (Phillips) ; Arkell : 91, pi. 7, fig. 4 ; pi. 9, fig. 8. 

1930. Entolium demissum (Phillips) ; Weir : 87, pi. 10, figs. 4, 9. 

1933. Pecten {Entolium) solidus Roemer ; Dietrich : 65, pi. 8, figs. 118, 119. 
1938. Entolium demissum (Phillips) ; Weir : 46, pi. 3, fig. 8. 
1948. Entolium corneolum (Young & Bird) ; Cox & Arkell : 15. 

Material. Several specimens. 

Localities and horizons. Kulong, 2 miles S.W. of Muddo Erri, N.E. Kenya ; 
Callovian [?-Lower Oxfordian], Muddo Erri Limestones. Wilderri hill, 11 miles 
S.S.W. of Rahmu, N.E. Kenya ; Upper Oxfordian, Seir Limestones. Manyuli 
stream, just W. of Nautope, Mandawa-Mahokondo anticline, Tanganyika ; Callo- 
vian. Scarp face, E. margin of Makoko plain, Bagamoyo hinterland, Tanganyika ; 
Upper Oxfordian. Hillside overlooking Lake Mbuo, Pindiro area, Tanganyika ; 
Middle Kimmeridgian. Valley and scarp at Kindope, N.N.W. of Tendaguru, Tang- 
anyika ; Upper Kimmeridgian, Nerinella and " Trigonia smeei " Beds. Kinjele, 5 
miles W. of Mtapaia, N. of Tendaguru, Tanganyika ; Upper Kimmeridgian, 
Indogrammatodon Bed. 

Remarks. Authors who have drawn a specific distinction between Pecten solidus 
Roemer and P. demissus Phillips have admitted that stratigraphical rather than 
morphological considerations have led them to do so. Mile C. Dechaseaux (1936 : 
61) has regarded them as synonymous. Arkell has shown that Pecten corneolus was 
the earliest name for the species commonly known as Entolium demissum. 

Entolium briconense (Cossmann) 
PL 6, fig. 6 

1907. Chlamys (Syncyclonema) briconensis Cossmann : 108, pi. 3, figs. 14, 15. 

1913a. Chlamys (Syncyclonema) briconensis Cossmann ; Cossmann : 3, pi. 1, fig. 20. 

1917. Chlamys (Syncyclonema) briconensis Cossmann ; Couffon : 120, pi. 4, fig. 1. 

1924. Syncyclonema briconense Cossmann ; Cossmann : 30, pi. 5, figs. 1, 2. 

Material. Three imperfect specimens (two in B.P. Coll.). 

Localities and horizons. Plantation \\ miles N. of Dakatcha village, Coast 
Province, Kenya ; in loose boulder. 2\ miles N. of Msaka road junction, Baga- 
moyo district, Tanganyika ; Callovian. 

Remarks. The specimens referred to this species, which was previously known 
only from the Callovian of France, have a characteristic ornament of concentric lines 
arranged in pairs a constant distance apart. They agree particularly well with the 



52 JURASSIC BIVALVIA AND GASTROPODA 

shell figured by Cossmann (1913a), who considers each pair of lines to mark the bases 
of attachment of concentric lamellae which formed the ornament of the uneroded 
shell. 

Entolium cingulatum (Goldfuss) 

PI. 6, fig. 5 

1836. Pecten cingulatus Goldfuss : 74 (partim), pi. 99, figs. 3a, b(}). 
1926. Entolium cingulatum (Goldfuss) ; Staesche : 93, pi. 4, figs. 3, 4. 

Material. One valve (counterparts), no. LL. 35202. 

Locality and horizon. 5 miles N.E. of Tengeni (village on Pangani river), at 
S. end of divide separating western tributary from main Maweni valley ; Upper 
Jurassic. 

Remarks. This specimen, a valve about 30 mm. high, clearly shows the two 
internal laminae, diverging from the beak and forming very acute angles with the 
dorsal margins of the body of the shell, which are characteristic of this and certain 
related species. There has been some difference of opinion as to the exact species to 
which Goldfuss's name cingulatus should be applied. In his original description 
Goldfuss attributed the species to Phillips and gave a reference to a figure published 
by that author (1829, pi. 5, fig. 11), representing a specimen from the Oxford Clay of 
England. Phillips, however, had merely recorded his specimen as Pecten sp. and for 
that reason it had been given the name Pecten phillipsii by Thurmann (1833 : 32). 
Thus Goldfuss, not Phillips, was the author of the name cingulatus, and when describ- 
ing the species he recorded it from localities belonging partly to the Lias and partly 
to the White Jura, without stating from which his figured specimens came. D'Orbigny 
(1850a : 238, 257) assigned the names Pecten philenor and P. proeteus to species found 
at different horizons of the Lias, in each case referring to Goldfuss's figures of P. 
cingulatus. Staesche has maintained that this action amounted to the restriction of 
Goldfuss's species to specimens from the White Jura, a doubtful conclusion, particu- 
larly in view of the fact that d'Orbigny did not adopt the name cingulatus for speci- 
mens from any horizon. The matter could be finally resolved only by the definite 
selection of one of Goldfuss's figured specimens as lectotype of P. cingulatus, if the 
specimens can be traced and their horizons are determinable. The name cingulatus 
is, however, now adopted in the sense advocated by Staesche, according to whom 
the species to which it is applied ranges throughout the White Jura in Germany. 
The Oxford Clay specimen figured by Phillips, holotype of Pecten phillipsii Thurmann, 
belonged to a species which is certainly distinct although not readily identified. 

Family PECTINIDAE Rafinesque 1815 

Genus EOPECTEN Douville 1897 

Eopecten aubryi (Douville) 
PL 6, figs. 3, 4 

1886. Pleuronectites aubryi Douville : 228, pi. 12, fig. 3. 

1929. Velata inaequi striata (Futterer) ; Weir : 25, pi. 1, fig 24 only, (non Futterer sp.). 



FROM TANGANYIKA AND KENYA 53 

*939- Velata aubryi (Douv.) ; Stefanini : 186, pi. 20, figs. 10, 11 ; pi. 21, fig. 1. 

1952. Eopecten aubryi (Douv.) ; Cox : 31, pi. 3, figs. 8-10. 

i960. Eopecten aubryi (Douv.) ; Joubert, pi. 8, figs. 1a, b. 

i960. Eopecten abjectus (Phillips) ; Joubert, pi. 7, fig. 7 (non Phillips sp.). 

Material. Several specimens, one ex B.P. Coll. 

Localities and horizons. 3! miles W. of Melka Biini, N.E. Kenya ; Callovian, 
Rukesa Shales. Muddo Erri, 12 miles W. of Rahmu, N.E. Kenya, Kulong, 2 miles 
to the S.W., and S. of Rahmu-Melka Murri road, 6 miles W. of Rahmu ; all Callovian 
[?-Lower Oxfordian], Muddo Erri Limestones. Manyuli stream, just W. of Nautope, 
Mandawa-Mahokondo anticline, Tanganyika ; Callovian. Mandawa-Lonji creek 
traverse, Mandawa area, Tanganyika ; Upper Oxfordian. 

Remarks. Specimens from N.E. Kenya are mostly quite typical of this species, 
as described in the works cited above, although the one figured under the name E. 
abjectus by Joubert (i960) has very unevenly spaced ribs. Those from the Upper 
Oxfordian of Tanganyika, while agreeing with the typical E. aubryi in the number, 
equality, and fairly regular distribution of the main radial ribs, differ in the almost 
complete smoothness of the intervals, which bear at the most a faint median riblet, 
finer interstitial threads being absent. There are insufficient grounds at present for 
distinguishing them even as a new sub-species, although they seem to be of rather 
later age than the hitherto recorded range (Bathonian-Lower Oxfordian) of E. 
aubryi. There are three specimens of the right valve of this species in the material 
studied, and their ornament consists of numerous fine, subequal, weakly granose 
radial riblets. 

Eopecten thurmanni (Brauns) 
PI. 6, fig. 8 

18506. Hinnites inaequistriatus d'Orbigny : 22 (ex Voltz MS. ; a secondary homonym of Lima 

inaequi striata Goldfuss, 1836, also an Eopecten). 
1862. Hinnites inaequistriatus d'Orb. ; Thurmann & Etallon : 267, pi. 37, fig. 13. 



1863 
1872 
1874 
1881 
1881 
1897 
1915 
1915 
1933 
1936 



Hinnites inaequistriatus d'Orb. ; Dollfus : 26, pi. 16, figs. 1-3. 

Hinnites inaequistriatus (Voltz) ; de Loriol : 391, pi. 23, figs. 1, 2. 

Hinnites thurmanni Brauns : 343. 

Hinnites inaequistriatus (Voltz) ; Boehm : 181, pi. 40, fig. 1. 

Hinnites gigas Boehm : 182, pi. 40, figs. 11, 12. 

Hinnites (Pleuronectites) inaequistriatus (Voltz) ; Futterer : 588, pi. 19, figs. 6, 7. 

Hinnites (Prospondylus) orbignyi Rollier : 464. 

Hinnites (Prospondylus) dollfusi Rollier : 465. 

Velata inaequistriata (Voltz) ; Dietrich : 67, pi. 8, fig. 129. 

Velata inaequistriata (Etal.) ; Dechaseaux : 71. 



Material. Two left valves (nos. L. 83900, L. 92195). 

Localities and horizons. 7 miles N.N.E. of Raiya hills, N.E. Kenya ; Upper 
Oxfordian, Seir Limestones. Hereri river crossing, 3 miles S. of Melka Kunha, N.E. 
Kenya ; Kimmeridgian, Hereri Shales. 

Remarks. One of these two specimens is remarkable for its size, its diameter 



54 JURASSIC BIVALVIA AND GASTROPODA 

being about 90 mm. It is a well-inflated valve, ornamented with a relatively small 
number (about 8) of rather unevenly spaced, prominent ribs, separated by wide 
intervals occupied by numerous radial threads which alternate in strength more or 
less regularly ; there is a slight tendency for the middle thread of each main interval 
to be more prominent than the others. This specimen seems to be larger than any 
hitherto recorded under the specific name inacquistriata, but it is smaller than 
Boehm's Hinnites gigas, a shell 155 mm. high. Notwithstanding the very irregular 
arrangement of its ribs, it is now suggested that Boehm's species should be considered 
a synonym of the inaequistriata of authors. The necessity for adopting Braun's 
name thurmanni for this species is indicated by the synonymy here given. The 
European range of this species is from the Upper Oxfordian to the Kimmeridgian. 

Eopecten aft", albus (Quenstedt) 
PL 6, fig. 7 

1836. aft. Spondylns velatus Goldfuss : 94, pi. 105, figs, ^a-d (secondary homonym of Pecten 

velatus Goldfuss, 1833 : 45, also an Eopecten). 
1857. aft. Pecten velatus albus Quenstedt : 628, pi. 78, fig. 3. 
1878 
1904 
1926 
1936 
i960 



aft. Hinnites astartinus Greppin ; de Loriol : 163, pi. 23, fig. 3. 
aft. Hinnites bonjouri de Loriol : 231, pi. 25, figs. 1,2. 
aft. Velopecten velatus (Goldfuss) ; Staesche : 122, pi. 6, fig. ir. 
aft. Velata bonjouri (de Loriol) ; Dechaseaux : 70, pi. 8, fig. 14. 
Eopecten cf. bonjouri (de Loriol) ; Joubert, pi. 8, fig. 2. 



Material. One specimen (no. L. 92247). 

Locality and horizon. Wilderri hill, 11 miles S.S.W. of Rahmu, N.E. Kenya ; 
Upper Oxfordian, Seir Limestones. 

Remarks. This specimen, a strongly convex left valve of an Eopecten, is only 
about 22 mm. high and not identifiable specifically with any certainty. There are 
about 13 rather irregularly spaced, weak, narrow principal radial costae which are 
separated by flat intervals ; a weak thread of secondary strength is present in one 
or two of these, but otherwise they appear smooth. It is probable that a few more 
ribs of primary strength would have appeared as the shell grew. The specimen 
bears some resemblance to de Loriol's fig. 2 of Hinnites bonjouri, a species considered 
by Staesche to be a synonym of the form to which he applies the name Velopecten 
velatus, a secondary homonym. The name albus Quenstedt is here accepted for the 
species. In Germany, according to Staesche, this ranges throughout the Malm, or 
Upper Jurassic. 

Genus CAMPTONECTES Meek 1864 
Camptonectes auritus (Schlotheim) 

1813. Chamites auritus Schlotheim : 103. 

1929. Chlamys (Camptonectes) lens (Sowerby) ; Weir : 25, pi. i, fig. 39. 

1930a. Camptonectes lens (Sowerby) ; Arkell : 94, pi. 7, fig. 1 ; pi. 9, figs. 4-7. 

1948. Camptonectes auritus (Schlotheim) ; Cox & Arkell : 14. 

i960. Camptonectes aurites [sic] (Schlotheim) ; Joubert, pi. 7, figs. },a-e. 



FROM TANGANYIKA AND KENYA 55 

Material. Several specimens. 

Localities and horizons. Kulong, 2 miles S.W. of Muddo Erri, also top of 
hills S. of Rahmu-Melka Murri road, 10 miles W. of Rahmu, N.E. Kenya ; Callovian 
[?-Lower Oxfordian], Muddo Erri Limestones. 2\ miles S.W. of Rahmu, N.E. 
Kenya ; Oxfordian, Rahmu Shales. Dusse, \\ miles S.E. of Rahmu; Upper Oxford- 
ian, Seir Limestones. 

Genus CHLAMYS Roding 1798 

Chlamys curvivarians (Dietrich) 

1929. Chlamys aff. palmyrensis (Krumbeck) ; Weir : 24, pi. i, figs. 34, 35. 

1929. Chlamys sp. ; Weir : 25, pi. 1, fig. 38. 

1933. Pecten [Chlamys) curvivarians Dietrich : 63, pi. 8, figs. 122, 123. 



1935a. Chlamys curvivarians (Dietrich) 

1939. Chlamys curvivarians (Dietrich) 

1952. Chlamys curvivarians (Dietrich) 

i960. Chlamys curvivarians (Dietrich) 



Cox : 176, pi. 18, figs. 14, 15. 
Stefanini : 183, pi. 20, fig. 9. 
Cox : 8, pi. 2, figs. 5, 8. 
Joubert, pi. 7, fig. 5. 



Material. Several specimens. 

Localities and horizons. 2 miles S. of Melka Biini, N.E. Kenya ; Bathonian, 
Murri Limestones. 3! miles W. of Melka Biini ; Callovian, Rukesa Shales. Ku- 
long, 2 miles S.W. of Muddo Erri ; also top of hills S. of Rahmu-Melka Murri road, 
10 miles W. of Rahmu, N.E. Kenya ; Callovian [?-Lower Oxfordian], Muddo Erri 
Limestones. Hereri river crossing, 3 miles S. of Melka Kunha, N.E. Kenya ; Kim- 
meridgian, Hereri Shales. Finno, Hegalu hills, N.E. Kenya ; Upper Kimmeridgian, 
Dakacha Limestones. 

Remarks. This species has been fully discussed in the papers cited. Its long 
range in East Africa is indicated by the occurrences stated above. 

Chlamys subtextoria (Miinster) 
PL 7, fig. 8 



1833 
1857 
1894 
1926 
1936 
1936 



Pecten subtextorius Miinster in Goldfuss : 48, pi. 90, figs. 11a, b. 

Pecten textorius albus Quenstedt : 627, pi. 77, figs. 25, 26. 

Pecten bipartitus Futterer : 32, pi. 5, figs. 4, \a. 

Chlamys subtextoria (Miinster) ; Staesche : 40 (partim) (non pi. 1, fig. 4). 

Chlamys subtextorius (Goldfuss) ; Dechaseaux : 19, pi. 3, fig. 2. 

tChlamys Etiveyensis (de Loriol) ; Dechaseaux, pi. 3, figs. 3, 4. 



Material. One specimen (no. L. 541 16). 

Locality and horizon. S. of Tarawanda, 11 miles S.E. of Lugoba, Tanganyika ; 
Callovian. 

Description. This specimen, a right valve about 22 mm. high, is characterized 
by its rather tall, trigonal outline, its slightly acute umbonal angle, and the relatively 
elongate dorsal margins of the disc. Its narrow, acutely angular costae, about 33 
in number, are distributed a little irregularly, with no pronounced tendency to be 



56 JURASSIC BIVALVIA AND GASTROPODA 

arranged in pairs. On the least eroded parts of the surface the ribs and their inter- 
vals are seen to be crossed by concentric lamellae. The upper margin of the anterior 
auricle slopes upward from the umbo. Growth stages of the inner margin of the 
subauricular notch are marked by a series of lamellae. 

Remarks. Staesche has placed Pecten etiveyensis de Loriol (1904, pi. 24, fig. 1) 
in the synonymy of C. subtextoria, but Mile Dechaseaux has regarded the two forms 
as distinct, stating that etiveyensis differs in the regularity, equality, and rounded 
(rather than angular) cross-section of its numerous ribs, points of distinction also 
emphasized by de Loriol when describing the species. By these criteria, Staesche's 
figured specimen of " subtextoria " would be referable to etiveyensis. Mile De- 
chaseaux's figures (pi. 3, figs. 3, 4) of specimens referred to etiveyensis rather contra- 
dict this distinction, however, as they indicate a decidedly irregular arrangement of 
the costae, which also appear to have broader intervals than in the typical etiveyensis. 
In its tall, trigonal form and acute umbonal angle the East African specimen now 
recorded more closely resembles the specimens which Mile Dechaseaux figures as 
etiveyensis than the one attributed to subtextoria, although the obtusely angular ribs 
are like those of the last specimen. It is possible that Staesche's broader conception 
of the species subtextoria is justified. The references given in the above synonymy 
are, however, to illustrations of specimens in which the ribbing is less regular and the 
intervals are broader than in the typical etiveyensis. Pecten bipartitus Futterer (1894 : 
32, pi. 5, figs. 4, 4a), from Oxfordian beds at Mkusi, 16 miles N.E. of Mtaru, Tangan- 
yika, does not seem to differ from C. subtextoria ; whereas it was described as having 
18-20 ribs, 30 can be counted in the figure. 

Chlamys matapwaensis sp. nov. 
PI. 7, figs. la, b, 2a, b 

Diagnosis. Small, subequivalve, of slight convexity, inequilateral, height (c. 11 
mm. in larger specimen) just exceeding length (10 mm.). Valves ornamented with 
22 or rather more slightly unevenly spaced, rounded, smooth riblets of moderate 
prominence, the outer ones curving outwards towards the adjacent margin ; the 
riblets may increase in number to a small extent during growth by dichotomy or by 
intercalation, the latter occurring mainly at a late growth-stage and only in some of 
the outer intervals. Intervals flat, their average width about the same as that of the 
riblets, ornamented with very fine concentric threads. Right posterior auricle 
obtusely triangular ; other auricles unknown complete ; byssal sinus unknown ; 
part of right anterior auricle closest to body of shell bearing series of closely spaced, 
equal threads perpendicular to the hinge-margin. 

Holotype and paratype. Nos. LL.35096, LL.35097 respectively (ex B.P. Coll.). 

Locality and horizon. N. of Matapwa, Pindiro area, Tanganyika ; Upper 
Kimmeridgian. 

Remarks. In Chlamys curvivarians (Dietrich), recorded above, the riblets are 
narrower and more numerous. 



FROM TANGANYIKA AND KENYA 57 

Subgenus RADULOPECTEN Rollier 1911 
Chlamys {Radulopecten) inequicostata (Young & Bird) 

PI. 7, ng. 5 

1822. Pecten inequicostatus Young & Bird : 236, pi. 9, fig. 7. 

1829. Pecten inaequico status Phillips : 129, pi. 4, fig. 10. 

1931a. Chlamys {Radulopecten) inaequico stata (Phillips) ; Arkell : 118, pi. 8, figs. 4-7 (also 

1935. pl- 52. ngs. i, 3). 
i960. Chlamys {Radulopecten) cf. inaequistriata (Phillips) ; Joubert, pl. 7, fig. 4. 

Material. One specimen (no. L.92228). 

Locality and horizon. Dusse, i| miles S.E. of Rahmu, N.E. Kenya ; Upper 
Oxfordian, Seir Limestones. 

Description. This specimen, which lacks the umbonal region and auricles and 
is rather eroded, was originally about 67 mm. high and 50 mm. long. The right 
valve has about six broad, depressed, rounded ribs which are separated by equally 
broad intervals ; ribs and intervals are crossed by fine, closely spaced, rather 
irregular, erect lamellae. The left valve has six ribs which are narrower than those 
of the right valve and are separated by intervals most of which are slightly broader 
than the ribs. One of the outer ribs on the anterior side bears short, spine-like 
projections, but details of the ornament are not preserved on the others. 

Remarks. The African specimen differs from most examples of the species from 
the Corallian Beds of England, the type occurrence, in the relative broadness of the 
intervals between the costae of the right valve, but in occasional specimens from 
England the intervals are just as broad. I see no reason, therefore, for separating 
the African specimen from C. inaequicostata, which is also known from France, 
Germany, Poland, and Switzerland. In Europe the species occurs in the Upper 
Oxfordian and Lower Kimmeridgian. 

Chlamys {Radulopecten ?) kinjeleensis sp. nov. 
Pl. 7, figs. 6a, b, ja, b 

Diagnosis. Shell small (height of holotype, the largest specimen, c. 13 mm.), 
suborbicular, subequivalve, moderately convex. Ornament consisting of about 10 
regularly arranged, broad, rounded radial costae, separated by slightly narrower, 
rounded intervals ; ribs and intervals crossed by concentric threads (removed by 
erosion except on a few small areas of the surface in the available specimens). Right 
anterior auricle small, bearing two weak radial riblets ; posterior auricles rather 
small, obtusely triangular. Byssal notch deep. 

Holotype and paratypes. Holotype, no. L. 5 1955, a right valve. Three para- 
types (including nos. L. 52145 and LL.35098, ex B.P. Coll.). 

Localities and horizons. N. of Kinjele, 5 miles W. of Mtapaia, N. of Tenda- 
guru, Tanganyika (type-locality) ; Upper Kimmeridgian, Nerinella Bed. Lilomba 



58 JURASSIC BIVALVIA AND GASTROPODA 

creek, Tendaguru, Tanganyika ; Upper Kimmeridgian, " Trigonia smeei " Bed. 
Mpilepile stream bed, near Mitole, and Kiwawa stream, both northern Mandawa 
area, Tanganyika ; Upper Kimmeridgian. 

Remarks. This species appears to be closely related to Chlamys (Radulopecten) 
inacquicostata, recorded above, but is much smaller and has more ribs. The speci- 
mens, although from four different localities, are all of about the same size, so that 
it has been assumed that they are full-grown. 



Subgenus SPONDYLOPECTEN Roeder 1882 

Chlamys (Spondylopecten ?) badiensis Cox 

PL 7, figs. 3, 4 
1952. Chlamys [Spondylopecten ?) badiensis Cox : 16, pi. 1, figs. 14a, b. 

Material. Two specimens (nos. L. 93552, LL. 35099), the latter ex B.P. Coll. 

Localities and horizon. Namakambe stream, Mandawa-Mahokondo anticline, 
Tanganyika ; probably Callovian. \ mile N.W. of bridge over Mkulumuzi river, 
2 miles W. of Tanga, Tanganyika ; Callovian. 

Description. Both specimens have 23 rounded, moderately prominent ribs, as 
in the holotype of C. badiensis. In one specimen the dorsal margins of the body of 
the shell are concave and extend almost to the middle of the height of the valve, 
the ventral margin of which forms a semicircle. In the second specimen the dorsal 
margins are relatively short, extending only to the dorsal third of the height of the 
valve, and the ventral margin is semi-elliptical. Although the two specimens thus 
differ considerably in outline, it is thought that they belong to the same species. In 
the first and less eroded specimen, a right valve 28 mm. high, the ribs bear a median 
and two lateral rows of small scales, together with regular, delicate transverse 
striations which are arched towards the umbo. The narrow, V-shaped intervals 
are also transversely striated and are bordered on each side by a longitudinal thread 
at the base of the adjacent rib. The second specimen, a left valve of about the same 
height, retains traces of similar ornament in places. The auricles are imperfect in 
both specimens, but can be seen to bear squamose or beaded radial riblets. 

Remarks. C. badiensis, the holotype of which came from the Callovian of Cutch, 
is closely related to the French Callovian species C. palinurus (d'Orbigny) (see 
Cossmann, 1913a : 2, pi. 11, figs. 1-4 ; 1924 : 29, pi. 5, figs. 5, 6), but in that species 
the number of ribs is only 20. Other related forms are C. syriaca Cossmann (1925 : 
325, pi. 8, figs, ya-c), with about 30 ribs, and C. macfadyeni Cox (1935a : 176, pi. 18, 
figs. 11a, b), with 19 ribs. All possibly could be geographical races of C. palinurus. 
The ligamental area of the right valve has not been observed in any of these forms, 
but their tentative reference to Spondylopecten is suggested by their external simi- 
larity to Pecten erinaceus Buvignier, its type species. 



FROM TANGANYIKA AND KENYA 59 

Genus WEYLA Boehm 1920 

Weyla ambongoensis (Thevenin) 
PI. 7, figs, ga, b, c 

19086. Pecten ambongoensis Thevenin : 24, pi. 4, figs. 2, 3. 

1948. Pecten ambongoensis Thev. ; Dubar : 220, pi. 29, figs. 7-9. 

Material. Numerous specimens. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. The specimens now recorded are quite typical of this species, which 
is known from the Upper Lias of Pakistan and Morocco as well as from the type- 
locality in Madagascar. 

Superfamily LIMACEA 

Family LIMIDAE Rafinesque 1815 

Genus LIMA Cuvier 1798 

Subgenus PLAGIOSTOMA J. Sowerby 1814 

Lima (Plagiostoma) biiniensis sp. nov. 
PL 8, fig. 1 

1929. Cf. Lima (Plagiostoma) cf. rigida Sow. ; Weir : 27, pi. 2, fig. 2. 
i960. Lima (Plagiostoma) sp. nov. ; Joubert, pi. 8, fig. 4. 

Diagnosis. Of medium size (height of holotype c. 53 mm.), suborbicular, 
slightly higher than long ; inflation even and moderate. Ventral margin strongly 
convex and not pronouncedly asymmetrical ; umbonal region obtusely angular in 
outline, its angle about 100 ° ; anterior umbonal ridge rounded off, relatively short. 
Main part of surface bearing numerous (probably about 70) radial riblets which 
project very little, are flat-topped in the holotype, and are separated by much 
narrower intervals which are seen to be punctate where the shell is least eroded. 
Auricles not preserved. 

Holotype. No. L. 92174. A few other specimens in the material studied may 
belong to the same species but are all imperfect and cannot rank as paratypes. 

Localities and horizons. 2 miles W. of Melka Biini, N.E. Kenya ; Bathonian, 
Murri Limestones. Possible representatives of the species from Kulong, 2 miles 
S.W. of Muddo Erri, N.E. Kenya ; Callovian [?-Lower Oxfordian], Muddo Erri 
Limestones. 

Remarks. The ornament of this species much resembles that of the Bajocian 
species L. semicircularis Goldfuss, discussed by the present writer (Cox 1943 : 160, 
pi. io, figs. 13, 14). The new species differs, however, in its more even inflation, its 
shorter and less marked anterior umbonal ridge, and its fewer radial ribs (their 
number is 80-90 in L. semicircularis). There are many records of L. semicircularis 



60 JURASSIC BIVALVIA AND GASTROPODA 

from the Bathonian, but not one where the recorded specimens are illustrated can be 
accepted. The specimen figured under this name by Morris & Lycett (1853, pi. 3, 
fig. 3) has been made the type of a new species L. bynei by Cox & Arkell (1948 : 17) 
and has fewer ribs than the form now described. Weir (1938, pi. 4, fig. 16) has 
figured a specimen from the Kambe Limestone (Upper Bajocian or Bathonian) of 
Kenya as L. cf. semicircularis. Its ribbing has been largely removed by erosion, but 
its outline resembles that of the species now described. 



Lima {Plagiostoma) cf. schardti de Loriol 

1883. Cf. Lima schardti de Loriol : 71, pi. 10, figs. 5— 11. 

i960. Lima (Plagiostoma) cf. schardti de Loriol ; Joubert, pi. 8, fig. 3. 

Material. Several imperfect specimens. 

Localities and horizons. Hills S. of Melka Murri-Rahmu road, 13 miles W. of 
Rahmu, N.E. Kenya ; Callovian, Rukesa Shales. Kulong, 2 miles S.W. of Muddo 
Erri, N.E. Kenya ; Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Remarks. In this species, originally described from the Mytilus Beds (Bathonian- 
Callovian) of Switzerland, the valves bear about 26 scaly ribs separated by intervals 
which are of the same width as the ribs over the greater part of the surface but become 
wider than them near the ventral margin. The ribs cannot be counted exactly in the 
specimens now recorded but their spacing is exactly as indicated in de Loriol's figures 
and their scaly character can be seen in places. The general outline of the shell is 
also as indicated by de Loriol. 



Lima {Plagiostoma) muddoensis sp. nov. 
PI. 8, fig. 2 
i960. Lima (Plagiostoma) cf. complanata Laube ; Joubert, pi. 8, fig. 5. 

Diagnosis. Of small-medium size (height of holotype c. 35 mm.), trapezoidal, 
length and height almost equal ; inflation rather weak in holotype, but this is 
probably partly due to compression in fossilization. Ventral margin moderately 
asymmetrical ; umbonal region not protruding, very slightly obtuse in outline, its 
angle about 100 ° ; anterior umbonal ridge rounded off, straight, forming an angle 
with the hinge-line which slightly exceeds 45 °. Lunule scarcely excavated. Poste- 
rior auricle relatively large, its outer angle only slightly obtuse ; anterior auricle not 
seen. Main surface bearing about 30 prominent, rounded ribs which are equal in 
strength and appear smooth except in late stages of growth, when they bear trans- 
verse imbrications. Intervals about same width as ribs and apparently without 
punctations. Posterior auricle with about 6 nodose radial ribs. 

Holotype. No. L. 92065 ; the material examined includes about two other 
specimens which probably belong to the same species but are too imperfect to rank 
as paratypes. 



FROM TANGANYIKA AND KENYA 61 

Locality and horizon. Muddo Erri, N.E. Kenya ; Callovian [?-Lower Oxford- 
ian], Muddo Erri Limestones. 

Remarks. This Lima, although rather similar to several previously described 
species, cannot be identified definitely with any of them. L. complanata Laube 
(1867 : 24, pi. 1, fig. 11), Callovian of Poland, has a narrower body and umbonal 
region, a smaller posterior auricle, and more ribs. In L. paolii Stefanini (1939 : 164, 
pi. 19, figs. 7, 8), from the " Lower Oolitic " of Somaliland, there are 36-38 ribs 
which are much more depressed than in the new species and have narrower intervals. 
In L. subcardiiformis Greppin, a widespread Bathonian species, the ribs are much 
more numerous. Of the varied series of Limidae occurring in the Bajocian of England, 
L. bradfordensis Cox (1943 : 159, pi. 9, fig. 10) is quite closely similar to the present 
species, but its ribs are relatively broader and their intervals narrower. L. notata 
Goldfuss (1836 : 83, pi. 102, figs. la, b), of the Upper Oxfordian and Kimmeridgian, 
is more equilateral in outline. 

Lima (Plagiostoma) cf. jumaraensis Cox 

1952. Cf. Lima {Plagiostoma) jumaraensis Cox : 52, pi. 5, figs. 4a, b, 5. 

Material. About four ill-preserved specimens. 

Locality and horizon. Kulong, 2 miles S.W. of Muddo Erri, N.E. Kenya ; 
Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Remarks. In this species, originally described from the Bathonian and Callovian 
of India, the narrow ribs are very depressed, projecting only slightly between the 
radiating linear grooves which separate them. In the specimens now recorded the 
ornament agrees well with that of the Indian ones, but not one is well enough pre- 
served to show the complete outline of the shell. The specimens from Somaliland 
recorded by Stefanini (1939 : 162, pi. 19, figs. 5a, b, 6a, b) as Lima [Plagiostoma) 
strigillata Laube are very similar to those now described, some of which were pro- 
visionally identified (Joubert i960 : 18) as Laube's species after comparison with 
Stefanini's figures. 

Lima {Plagiostoma) rahmuensis sp. nov. 
PI. 7, figs, iofl, b 

Diagnosis. Of medium size (height of holotype c. 35 mm.), trapezoidal, slightly 
higher than long, well inflated. Ventral margin moderately asymmetrical ; um- 
bonal region obtusely angular in outline, its angle about 120° ; anterior umbonal 
ridge rounded off, straight, not greatly elongated, forming an angle of about 45 ° 
with the hinge-margin ; lunule well excavated. Main part of surface bearing 
numerous punctate linear radial grooves, about 7 of which occcupy a width of 5 mm. 
near the ventral margin ; spaces between grooves quite flat. 

Holotype. No. L. 83892. The only specimen. 

Locality and horizon. z\ miles S.W. of Rahmu, N.E. Kenya ; Oxfordian, 
Rahmu Shales. 



62 Jl'RASSIC BIVALVIA AND GASTROPODA 

Remarks. This species closely resembles Lima (PI agio stoma) punctata J. Sowerby, 
of the Lias. Of comparable Upper Jurassic species, L. boidini Sauvage (de Loriol 
1875 : 171, pi. 21, figs. 8, 9), Portlandian of northern France, is elongated in a more 
oblique direction and its punctate grooves are more broadly spaced. L. libanensis 
Krumbeck (1905 : 99, pi. 10, fig. 5), Lower Kimmeridgian of Syria, is described as 
having distinctly raised but at the same time very depressed ribs, although this is not 
obvious in the figures. L. harronis Dacque (1905 : 133, pi. 15, figs. 13, 14), Kim- 
meridgian of Somaliland, is a narrower and more oblique shell with distinctly raised 
ribs. L. thisbe de Loriol (1888 : 322, pi. 36, figs. 1-4), Lower Kimmeridgian of the 
French Jura, and L. burensis de Loriol (1893 : 331, pi. 34, figs, n, 12 ; 1895 : 47, 
pi. 9, fig. 2) and L. trembiazensis de Loriol (1901 : 102, pi. 5, fig. 24), both from the 
Upper Oxfordian of the Swiss Jura, have distinctly raised ribs separated by punctate 
grooves which are more closely spaced than in the form now described. 

Lima {Plagiostoma) sublaeviuscula Krumbeck 
PL 8, figs. 5, 6 

1905. Lima sublaeviuscula Krumbeck : 99, pi. 3, figs. 3a, b. 

Material. Two specimens. 

Locality and horizon. 5 miles S. of Galgali Gambo, N.E. Kenya ; Upper 
Kimmeridgian, Dakacha Limestones. 

Remarks. These specimens, the larger of which is about 80 mm. high, are larger 
than Krumbeck's type-specimen, but are similar to it in shape and have exactly the 
same characteristic ornament of very depressed radial ribs which are unequal and 
irregularly spaced, and are confined to the anterior, posterior and ventral parts of 
the surface, the middle of which is smooth. The intervals between the ribs are 
relatively narrow and do not seem to be punctate. It seems doubtful if L. informis 
Krumbeck (1905 : 100, pi. 3, figs, ya-c) is specifically distinct from L. sublaeviuscula, 
although stated to be less inequilateral, higher in proportion to its breadth and more 
gibbose, and to have a shorter and broader lunule. Both forms, described originally 
from the Lower Kimmeridgian of Syria, differ only in minor details from the Upper 
Oxfordian species L. laeviuscula (J. Sowerby), in which the shell seems to be slightly 
broader and the ribs less numerous. A specimen (L. 92235) from the Seir Limestones 
(Oxfordian) of N. Kenya identified (Joubert i960, pi. 8, fig. 6) as Lima (Plagiostoma) 
cf. laeviuscula may well belong to Sowerby's species, but is broken anteriorly and too 
imperfect for definite identification. 

Subgenus ACESTA Adams 1858 

Lima (Acesta) kindopeensis sp. now 

PI. 8, fig. 10 

Diagnosis. Of medium size (height of holotype c. 47 mm.), ovate-trapezoidal, 
with a slight lunate tendency ; length, parallel to hinge-margin, almost equal to 



FROM TANGANYIKA AND KENYA 63 

height ; posterior margin short, ventral margin strongly asymmetrical, feebly con- 
vex posteriorly, strongly convex anteriorly. Inflation weak. Umbonal region 
sharply rounded in outline, its angle less than a right angle. Anterior umbonal 
ridge rounded off, fading away before reaching somewhat upturned antero-ventral 
part of shell. Lunule short, well excavated. Posterior auricle small and obtuse, 
anterior auricle virtually absent. Ornament consisting of 43 broad, depressed ribs 
which are interrupted by irregularly and rather distantly spaced growth-rugae and 
in the holotype are deflected in an anterior direction at the stage when the shell was 
about three-quarters fully grown. Intervals between ribs narrow and shallow, 
apparently not punctate. 

Holotype. No. L. 56240. The only specimen. 

Locality and horizon. Kindope, N.N.W. of Tendaguru, Tanganyika ; Upper 
Kimmeridgian, Nerinella Bed. 

Remarks. Although much of the holotype is an internal mould, the original 
shell is preserved in places, particularly in the antero-ventral region. This species 
is comparable to L. monsbeliardensis Contejean (de Loriol 1872 : 377, pi. 22, figs. 2, 
2a), from the Lower Kimmeridgian of Europe, but has fewer ribs and also differs in its 
somewhat lunate outline. In L. virgulina Contejean (i860 : 308, pi. 23, figs. 1, 2), 
another rather similar species from the Kimmeridgian of Europe, the ribs are even 
more numerous. In L. meroe de Loriol (1894a : 151, pi. 10, figs. 17, 18), Lower 
Kimmeridgian of France, there are about 60 ribs and a distinct anterior auricle is 
present. 

Lima (Acesta) cutleri sp. nov. 

PI. 8, fig. 9 

Specific name. After the late W. E. Cutler, the first leader of the British Mu- 
seum East Africa Expedition. 

Diagnosis. Relatively small, narrowly subovate, broadening ventrally, and 
with a slight lunate tendency ; height much exceeding length ; inflation moderate. 
Posterior and ventral margins forming an uninterrupted curve, the lower part of 
which is strongly and asymmetrically convex ; anterior margin very slightly con- 
cave. Umbonal region narrow, no distinct umbonal ridges ; no lunule. Posterior 
auricle obtuse, not distinctly delimited from body of shell ; anterior auricle virtually 
absent. Ornament consisting of slightly sinuous, punctate, linear grooves, the 
intervals between which are flat and do not form distinct ribs except on anterior part 
of surface, where they are slightly elevated. Grooves close together on posterior 
part of surface but more widely spaced on anterior part ; their total number exceeds 
60. There are also a few well-marked and very irregularly distributed growth- 
rugae. 

Holotype and paratypes. Holotype, no L. 52033. There are several paratypes. 

Localities and horizon. Tingutitinguti creek (type-locality) ; Nitongola 
creek, and Kindope valley, all near Tendaguru, Tanganyika ; Upper Kimmerid- 
gian, " Trigonia smeei " Bed. 



64 JURASSIC BIVALVIA AND GASTROPODA 

Remarks. This shell is much narrower than L. kindopeensis sp. nov., described 
above, and also differs in the absence of a distinct anterior umbonal ridge and lunule 
and of distinct radial ribs except on the anterior part of the surface. 



Genus PSEUDOLIMEA Arkell 1932 

Pseudolimea duplicata (J. de C. Sowerby) 
PI. 8, figs. 8a, b 

1827a. Plagiostoma duplicata J. de C. Sowerby : 114, pi. 559, fig. 3. 

1932a. Lima (Pseudolimea) alternicosta Buvignier ; Arkell : 140, pi. 13, figs. 3-5. 

1933. Lima (Radula) sp. ; Dietrich : 63, pi. 7, figs. 96-98. 

1944a. Pseudolimea duplicata (Sow.) ; Cox : 84. 

1952. Pseudolimea duplicata (Sow.) ; Cox : 60, pi. 5, figs. 11, 12. 

Material. Several specimens. 

Localities and horizons. Kulong, 2 miles S.W. of Muddo Erri, N.E. Kenya ; 
Callovian [?-Lower Oxfordian], Muddo Erri Limestones. Dusse, i| miles S.E. of 
Rahmu, N.E. Kenya ; Upper Oxfordian, Seir Limestones. Kindope, N.N.W. of 
Tendaguru, Tanganyika ; Upper Kimmeridgian, Nerinella Bed. 

Remarks. The Pseudolimea which occurs in some abundance at Tendaguru and 
was recorded as Lima [Radula) sp. by Dietrich does not appear to be distinguishable 
specifically from the long-ranging species P. duplicata, the synonymy of which is 
given in my two papers cited above. The largest Tendaguru specimens are, indeed, 
only 13 mm. high and thus smaller than specimens from many localities, but the 
general proportions of the shell, the number of ribs (22) and their V-shaped cross- 
section, and the presence of a radial thread in each interval are exactly as in P. 
duplicata. The specimens from lower horizons in northern Kenya are in every way 
typical. The known range of the species in Europe is from Toarcian to Upper 
Oxfordian, with an unconfirmed record from the Portlandian. 



Pseudolimea mandawaensis sp. nov. 
PI. 8, fig. 3 

Diagnosis. Large for a Pseudolimea, broadly trapeziform, length and height 
about equal (c. 40 mm.), ventral margin strongly asymmetrical, umbonal region 
slightly obtuse. Postero-dorsal region only slightly impressed ; auricles unknown. 
Main ribs about 23, obtusely angular, depressed, with broadly rounded, slightly un- 
equal intervals bearing numerous fine, unevenly spaced radial threads with one near 
middle slightly more prominent than the others ; in addition, a few weak, jagged radial 
riblets occupy anterior and posterior ends of shell. Concentric ornament, except 
near ventral margin, consisting of closely and evenly spaced threads which are even 
more delicate than the radials ; late growth stages, however, are marked by irregular 
concentric rugae. 



FROM TANGANYIKA AND KENYA 65 

Holotype. No. LL. 35100, ex B.P. Coll. The only specimen. 

Locality and horizon. Lihimaliao creek, Mandawa area, Tanganyika ; Upper 
Oxfordian. 

Remarks. The original convexity of the holotype, a rather crushed specimen, 
does not appear to have been very strong. The ornament recalls that of the two 
Liassic species Pseudolimea pectinoides (J. Sowerby) and P. roemeri (Brauns), and, 
although its internal characters are unknown, the species is referred to Pseiidolimea 
with some confidence. Lima mistrowitzensis Boehm (1883 : 638, pi. 69, figs. 21, 22), 
from the Tithonian Stramberg beds, is a comparable species, but has fewer radial 
ribs. 

Genus LIMATULA Wood 1839 

Limatula moorei sp. nov. 

PL 8, figs, ya, b 

Specific name. After Mr. W. R. Moore, of the Tanganyika Geological Survey, 
collector of the holotype. 

Diagnosis. Small (height 9-0 mm., length 7-0 mm.), tall, ovate, slightly asym- 
metrical, with prominent umbo ; surface evenly inflated. Ornament confined, as 
in all Limopsis, to median part of flank, and consisting of smooth, rounded, not very 
prominent ribs separated by intervals which are only about one-third as wide as 
ribs and bear delicate growth-threads near ventral margin. Ribbed part of surface 
merges gradually on both sides into smooth anterior and posterior parts ; number 
of ribs, apart from very weak outer ones, about 15. 

Holotype. No. LL. 16799, a right valve. The only specimen. 

Locality and horizon. Usigiwa river, 6 miles W.S.W. of Kiwangwa, Baga- 
moyo hinterland, Tanganyika ; Upper Oxfordian. 

Remarks. The broadly rounded ribs and narrow intervals distinguish this form 
from most of the species of Limatula described previously from the Middle and Upper 
Jurassic, including L. boehmi de Loriol, L. consobrina (d'Orbigny), L. gerassimovi 
Pchelintsev, L. gibbosa (J. Sowerby), L. globularis Laube, L. helvetica (Oppel), L. 
oxfordiana Maire, L. praedispersa Krause, and L. rauracica Cossmann. In L. 
minutissima (d'Orbigny) ( = Lima minuta Roemer non Goldfuss ; synonym, Lima 
suprajurensis Contejean) the ribs are just as broad as in the species now described, 
but they are scaly or tuberculate, while the shell itself is more distinctly truncated 
posteriorly. 

Limatula migeodi sp. nov. 
PI. 8, figs. 4«, b 

Specific name. After the late F. W. H. Migeod, for some years leader of the 
British Museum East Africa Expedition. 

Diagnosis. Small (height of holotype 10-5 mm.), ovate, breadth nearly three- 
quarters of height ; slightly oblique. Auricles moderately large, obtuse-angled, the 



66 JURASSIC BIVALVIA AND GASTROPODA 

posterior slightly the larger. Median part of valve ornamented with 13 angular 
costae which are separated by slightly narrower, angular intervals and bear small, 
evenly spaced nodes. Ribbed area sharply separated from anterior and posterior 
parts of surface, which are smooth except for a few faint radial lines and growth- 
lines. 

Holotype and paratype. Nos. LL.11514, LL.11515 respectively. 

Locality and horizon. Kindope, N.N.W. of Tendaguru, Tanganyika ; Upper 
Kimmeridgian, Nerinella Bed. 

Remarks. A species Limatula tendagurensis Lange (1914 : 207, pi. 15, figs. 6a, b) 
was described from the Neocomian of Tendaguru, and Dietrich (1933 : 63) has stated 
that it ranges throughout the whole series of beds at that locality. The Jurassic 
form now described differs, however, from Lange 's figures in its more strongly con- 
vex anterior and posterior margins and its broader proportions. It also has fewer 
ribs, the number mentioned by Lange being 15-17 in addition to some weaker ones 
which extend on to the lateral parts of the surface. 



Genus CTENOSTREON Eichwald 1862 
Ctenostreon proboscideum (J. Sowerby) 

1820a. Lima proboscidea J. Sowerby : 115, pi. 264. 

1932a. Ctenostreon proboscideum (Sowerby) ; Arkell : 145, pi. 15, fig. 3. 

1937. Ctenostreon proboscideum (Sowerby) ; Hennig : 180. 

i960. Ctenostreon proboscideum (Sowerby) ; Joubert : pi. 8, fig. 7. 

Material. One specimen (no. L.92184). 

Locality and horizon. Melka Dakacha, N.E. Kenya ; Upper Kimmeridgian, 
Dakacha Limestones. 

Remarks. The specimen now recorded is a relatively small, ill-preserved internal 
mould with about nine radial ribs. The species was recorded by Hennig from beds 
thought to be Kimmeridgian in age at a locality in the Mandawa district of Tangan- 
yika. 

Superfamily OSTREACEA 

Family OSTREIDAE Rafinesque 1815 

Genus LOPHA Roeding 1798 

Lopha costata (J. de C. Sowerby) 
PI. 9, figs, la, b, c 

1825a. Ostrea costata J. de C. Sowerby : 143, pi. 488, fig. 3. 
1853. Ostrea costata Sow. ; Morris & Lycett : 3, pi. 1, figs. 5, 5a. 
1856. Ostrea costata Sow. ; Quenstedt : 497, pi. 66, figs. 43, 44. 
1863. Ostrea costata Sow. ; Martin : 65, pi. 5, figs. 12-15. 
1868. Ostrea costata Sow. ; Lycett, pi. 34, fig. 3. 



FROM TANGANYIKA AND KENYA 67 

1883. Ostrea costata Sow. ; de Loriol : 77, pi. 11, figs. 8-17. 

1888. Ostrea (Alectryonia) costata Sow. ; Schlippe : 113, pi. 1, figs. 11, 12. 

1912. Alectryonia costata Sow. ; Lissajous : 65, pi. 8, figs. 19, 20. 

1916. Ostrea {Alectryonia) costata Sow. ; Jekelius : 230, pi. 4, figs. 3-6 ; pi. 6, fig. 9. 

1923. Alectryonia costata Sow. ; Cossmann : 4, pi. 5, figs. 5-8. 

1924. Ostrea costata Sow. ; Cossmann : 24, pi. 2, figs. 61-64. 
1924. Ostrea (Alectryonia) costata Sow. ; Hennig : 33, pi. 3, fig. 2. 
1929. Arctostrea costata (Sow.) ; Weir : 21, pi. 1, fig. 17. 

1933. Ostrea (Alectryonia) costata Sow. ; Ruiz, in Fabiani & Ruiz : 14, pi. 2, fig. 1. 
19346. Lopha costata (Sow.) ; Arkell : 48, pi. 1, figs. 3-6. 
1935. Lopha costata (Sow.) ; Cox : 173, pi. 17, fig. 13. 

Material. One specimen (no. LL. 35025) from the Toarcian and several from 
later beds. 

Localities and horizons. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 3! miles W. of Melka Biini, N.E. Kenya ; 
Callovian, Rukesa Shales. S. of Rahmu-Melka Murri road, 6 miles W. of Rahmu, 
N.E. Kenya ; Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Description. The Toarcian specimen now recorded is about 17 mm. high, with 
a deep lower valve, the sides of which rise steeply from a rather large attachment 
area. The sides have about 13 irregularly arranged costae, some of which have 
arisen during growth by bifurcation of single costae, and which are prominent except 
on the posterior and anterior ends of the valve. The costae are rounded at their 
crests and are separated by deep but rounded intervals of about their own average 
width. The upper valve is flat except for some irregularities and has a few weak 
radial plications. The specimens from later formations call for no particular com- 
ment. 

Remarks. I have hesitated before referring the Upper Liassic specimen to L. 
costata, as typically this is a Bathonian species and records of its occurrence even as 
early as the Bajocian have been queried (Whidborne 1883 : 492). Specimens from 
the Bajocian of the Cotswolds which I would refer to the species are, however, in the 
British Museum (Natural History). In typical specimens from the Great Oolite of 
England, such as those figured by Morris & Lycett (1853) and by Arkell (1934&), the 
plications are smaller and more numerous than in the specimen now recorded, and 
this is also the case in European Bathonian specimens figured by Schlippe (1888) and 
Cossmann (1923). In those figured by Lissajous (1912), however, the ribbing is of 
about the same strength as in the present shell, and this is also the case in the English 
Inferior Oolite specimens already mentioned. Cossmann (1924) has referred to the 
variability of specimens of L. costata from the French Callovian, and has stated that 
the number of ribs ranges from 12 to 18 irrespective of the geological horizon. L. 
costata is here accepted as a species ranging from Toarcian to Callovian, the present 
being the first record of its occurrence in the former stage. Thevenin (19086 : 21, 
pi. 4, figs. 10, iofl) has recorded a small plicated oyster from the Upper Lias of 
Madagascar under the name Ostrea subserrata Goldfuss, although Goldfuss's species 
is now known to have been a Plicatula. The specimen from Madagascar has narrow- 



68 JURASSIC BIVALVIA AND GASTROPODA 

and, apparently, more lamellose plications than the shell now recorded ; it most 
probably also belongs to L. costata. 



Lopha olimvallata nom. nov. 

PL 9, figs. 2a, b 

1874. Ostrea vallata Dumortier : 203, pi. 45, figs. 7, 8 (non Thurmann & Etallon, 1862). 

1905. ? Ostrea sp. ; Benecke : 161, pi. 12, fig. 12. 

1929. Alectryonia vallata Dumortier ; Schafle : 64, pi. 6, figs. 6-8. 

1935. Alectryonia vallata Dumortier ; Kuhn : 119, pi. 8, fig. 30. 

Material. One specimen (no. LL. 35026). 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Description. This specimen is an elongated, linguiform, shallow left valve 51 
mm. high and 20 mm. broad, attached by almost its entire surface to a lamina of 
fibrous calcite, to the other side of which some smaller and less complete right valves 
are attached. The low sides of the valve rise steeply from the attachment area and 
have a number of rather weak, irregular plications. The umbo is directed in an 
anterior direction to a slight extent. 

Remarks. In the type-specimen of Ostrea vallata, which came from the Upper 
Lias of southern France, and in specimens from the Upper Lias of Germany figured 
by Schafle, the height of the shell is only slightly in excess of the breadth. In the 
shell from the Aalenian of Lorraine figured by Benecke as " Ostrea sp. ", and con- 
sidered by Schafle to belong to Dumortier's species, the shape is narrow and lingui- 
form and the umbo is directed anteriorly exactly as in the specimen now recorded, 
although the plications of the shallow sides of the valve are stronger and more 
numerous. The present specimen is thought to be referable to Dumortier's species 
as interpreted by Schafle and now renamed. 



Lopha gregarea (J. Sowerby) 
PI- 9. ng. 5 

1815a. Ostrea gregarea J. Sowerby : 19, pi. 111, figs. 1, 3. 

1933a. Lopha gregarea (Sowerby) ; Arkell : 183, pi. 22, figs. 5, 6 ; pi. 23, figs. 1-4. 

1952. Lopha gregarea (Sowerby) ; Cox : 96, pi. 4, fig. 2 ; pi. 10, figs. 7-13. 

i960. Lopha gregarea (Sowerby) ; Joubert, pi. 9, fig. 1. 

Material. Several specimens. 

Localities and horizons. 3! miles W. of Melka Biini ; also hills S. of Rahmu- 
Melka Murri road, 11 miles and 13 miles W. of Rahmu, N.E. Kenya ; Callovian, 
Rukesa Shales. S. of Rahmu-Melka Murri road, 6 miles W. of Rahmu, N.E. 
Kenya ; Callovian [?-Lower Oxfordian], Muddo Erri Limestones, if miles S.W. of 
Rahmu and 6| miles S.S.W. of Rahmu, N.E. Kenya ; Oxfordian, Rahmu Shales. 
Wilderri hill, 11 miles S.S.W. of Rahmu, N.E. Kenya ; Upper Oxfordian, Seir 



FROM TANGANYIKA AND KENYA 69 

Limestones. 3 miles N.E. of Melka Dakacha, N.E. Kenya ; Upper Kimmeridgian, 
Dakacha Limestones. i£ miles E. of Kidugallo Station, Central Railway, Tangan- 
yika ; Bajocian, Station Beds. 



1821 

1857 
1930 

1938 
1952 



Lopha eruca (Defrance) 

Ostrea eruca Defrance : 31. 

Ostrea hastellata [rastellata] Quenstedt : 750, pi. 91, figs. 26, 27. 

Arctostrea hastellata (?non Quenstedt ; de Loriol) ; Weir : 85, pi. 9, fig. 4. 

Lopha krumbecki Weir : 45, pi. 3, fig. 7. 

Lopha eruca (Defrance) ; Cox : 103, pi. 11, figs. 1-7. 



Material. One internal mould (no. LL.35101), ex B.P. Coll. 

Locality and horizon. \ mile from Msata on road to Bagamoyo, Tanganyika ; 
Callovian or Oxfordian (in friable brown sandstone). 

Remarks. Although merely an internal mould, this specimen undoubtedly be- 
longs to Defrance's species, the full synonymy of which is given in my paper cited 
above. There is little doubt that the specimens from Kenya recorded by Weir 
(1930, 1938) belong to this species. 

Lopha cf. intricata (Contejean) 
PI. 9, figs. 8a, b 
i860. Cf. Ostrea intricata Contejean : 323, pi. 25, figs. 6-8. 

Material. One specimen (no. L. 83899). 

Locality and horizon. b\ miles S.S.W. of Rahmu, N.E. Kenya ; Oxfordian, 
Rahmu Shales. 

Remarks. This is a tall, oval, slightly oblique and lunate, weakly inflated speci- 
men, 44 mm. in height and 28 mm. broad, with a large attachment area from which 
the walls of the lower valve, folded into plications of small amplitude, rise vertically 
to the commissure. The upper valve, which has an irregular surface, is weakly con- 
vex and also plicated at its margins. Except that its lower valve is not quite so deep, 
this specimen agrees well with Contejean's figure of the holotype of Ostrea intricata, 
a specimen of Lower Kimmeridgian age. In 0. vallata Etallon (de Loriol 18946 : 75, 
pi. 9, figs. 5, 6), from the Swiss Oxfordian, the plications are sharper and more num- 
erous. It is difficult to say whether or not these specimens are merely examples of 
better-known species of Lopha in which the development of plications on both 
valves has been restricted by an unusually large attachment-area. 

Lopha solitaria (J. de C. Sowerby) 
PI. 9, fig. 4 

1824a. Ostrea solitaria J. de C. Sowerby : 105, pi. 468, fig. 1. 

1933a. Lopha solitaria (Sowerby) ; Arkell : 185, pi. 22, fig. 4 ; pi. 23, figs. 5-7. 

1935a. Lopha solitaria (Sowerby) ; Cox : 171, pi. 17, figs. 9-12. 

i960. Lopha solitaria (Sowerby) ; Joubert, pi. 9, figs. 2a-c. 



■jo J I RASSIC BIVALVIA AND GASTROPODA 

Material. Several specimens. 

Localities and horizons, if miles S.W. of Rahmu, N.E. Kenya, and river 
section W. of Rahmu-El Wak road, 5^ miles S.W. of Rahmu ; Oxfordian, Rahmu 
Shales. Golberobe hills, N.E. Kenya ; Oxfordian, Golberobe Beds. Dusse, i\ 
miles S.E. of Rahmu, N.E. Kenya, and Wilderri hill, 11 miles S.S.W. of Rahmu ; 
Upper Oxfordian, Seir Limestones. Chamgamwe, near Mombasa, Kenya ; Kim- 
meridgian, Chamgamye Shales. 

Lopha tifoensis sp. nov. 
PI. 10, figs. 1, 2, 6, 7 

1957. Lopha sp. ; Saggerson & Miller : 20, fig. e. 

Diagnosis. Shell small (height of largest specimen 27 mm.), trigonal to ovate, 
variable in proportions but usually higher than long, with deep but relatively thin- 
shelled lower valve and flat upper valve. Attachment-area conspicuous, fairly large 
in some specimens, terminal, truncating the umbonal region. Surface of lower valve 
with a series of irregularly distributed, rounded costae, some fading away during 
growth while others appear by intercalation and bifurcation, diverging to margins 
from points close to attachment-area. Where they first appear the number of 
costae is about 4-6 ; in the holotype, a specimen 14 mm. high, and in the largest 
paratype, mentioned above, the number of costae reaching the margin is about 10, 
but in another specimen, 18 mm. high, the number is 16. Upper valve with de- 
pressed, rounded radial costae originating at same stage of growth as in lower valve. 

Holotype and paratypes. Holotype, no. L. 93574 ; several paratypes, of 
which L. 93561, L. 93563 and L. 93580 are figured. 

Localities and horizon. Tifo (type-locality), Korkai Hammassa, Ogar Wein, 
Chimpa, and Asahaba, all N.E. Kenya ; Oxfordian, Golberobe Beds. 

Remarks. While in most specimens the height considerably exceeds the length, 
the specimen represented in fig. 2 is remarkable for its quadrate outline. Its 
attachment-area is unusually large and its ribs very weak. Some specimens of this 
species were originally identified as Lopha costata (J. de C. Sowerby), to which it 
appears to be closely related. It differs from Sowerby's species, however, in its much 
more depressed and rounded costae. 

Lopha ? kindopeensis sp. nov. 
PI. 10, figs. 3, 4a, b, 5 

Diagnosis. Moderately large (height of holotype 96 mm.), trapezoidal, typically 
with more or less straight anterior and posterior margins diverging from the base of 
a broad ligamental area, and tending to be subangular postero-ventrally. Both 
valves fairly thick-shelled and almost flat, differing very little in convexity. (The 
left valve, however, is known only by imperfect specimens mostly growing attached 
to the greater part of the surface of right valves, the exteriors of which are thus 



FROM TANGANYIKA AND KENYA 71 

obscured although their interiors are well exposed.) Adductor scar large. Margins 
of both valves with rounded, unevenly spaced plications which scarcely extend on 
surface of shell even where this is not obscured by adherent specimens. In one 
specimen which appears to be a left valve (although this is not altogether certain as 
its dorsal half is broken away) the somewhat eroded surface bears unevenly arranged, 
discontinuous pustules and superficial ribs. 

Holotype and paratypes. Holotype, no. L. 54855 ; four paratypes, of which 
L. 54856 and L. 54858 are figured. 

Localities and horizon. Kindope (type-locality), and N. of Kinjele, both near 
Tendaguru, Tanganyika ; Upper Kimmeridgian, Nerinella Bed. 

Remarks. This form, with its weak plications confined to the margins, appears 
to lie on the border-line between Ostrea and Lopha. It is much larger but relatively 
less inflated than Lopha intricata (Contejean), referred to above, and also differs in 
its angular outline. 

Lopha hennigi (Dietrich) 
*933- Alectryonia hennigi Dietrich : 70, pi. 10, figs. 144, 145. 

Material. Several specimens. 

Localities and horizons. Mtapaia road and Kipande path, near Tendaguru, 
Tanganyika ; Upper Kimmeridgian, " Trigonia smeei " Bed. Kindope, near 
Tendaguru, Tanganyika ; Upper Kimmeridgian, Nerinella Bed. 

Remarks. This is a large, thick-shelled oyster with strong, angular, unequal 
plications, bifurcating in places. It is closely related to the widespread Jurassic 
species L. marshii (J. Sowerby), which occurs at lower horizons in East Africa, but 
is represented only by poor and somewhat doubtful specimens in the material 
studied. 

Genus LIOSTREA Douville 1904 
Liostrea dubiensis (Contejean) 

i860. Ostrea dubiensis Contejean : 320, pi. 21, figs. 4-1 1. 

I935 a - Ostrea (Liostrea) dubiensis Contejean ; Cox : 171, pi. 17, figs. 4, 5. 

Material. Numerous specimens. 

Localities and horizons, i mile and 2 miles W. of Magindu Station, Central 
Railway, Tanganyika ; about Bathonian. 1 mile N. of Asaharbito, N.E. Kenya ; 
Bathonian [? or Callovian], Asaharbito Beds. Ogar Wein and Golberobe hills, N.E. 
Kenya ; Oxfordian, Golberobe Beds. Dusse, 1^ miles S.E. of Rahmu, N.E. Kenya ; 
Upper Oxfordian, Seir Limestones. Kiwato-Mkange track, 5 miles S.S.E. of Mkange, 
Bagamoyo hinterland, Tanganyika ; Oxfordian or Kimmeridgian. Tingutitinguti 
creek and Kindope, both near Tendaguru, Tanganyika ; Upper Kimmeridgian, 
" Trigonia smeei " and Nerinella Beds. 



7 J JURASSIC BIVALVIA AND GASTROPODA 

Liostrea polymorpha (Miinster) 
PL 9, figs. 3, ya, b 



1833 
1835 
1843 
1857 
1878 
1881 
1917 
1931 



Gryphaea polymorpha Miinster, in Goldfuss : 31, pi. 86, figs, la, b. 

" Unbestimmt "; Roemer, pi. 3, fig. 12. 

Ostrea romeri Quenstedt : 434. 

Ostrea romeri Quenstedt ; Quenstedt : 625, pi. 77, figs. 22, 23 (?). 

Ostrea roemeri Quenstedt ; de Loriol : 165, pi. 23, fig. 4. 

Ostrea roemeri Quenstedt ; de Loriol : 96, pi. 13, fig. 7. 

Ostrea polymorpha (Miinster) ; Rollier : 592. 

Gryphaea roemeri (Quenstedt) ; Pchelintsev : 67. 



Material. Three specimens, including nos. LL. 35 102-03, a U ex B.P. Coll. 

Locality and horizon. Lihimaliao creek, Mandawa area, Tanganyika ; Upper 
Oxfordian. 

Remarks. Ostrea roemeri is included in the synonymy of Gryphaea polymorpha 
on the authority of Rollier and Pchelintsev. G. polymorpha has been misinterpreted 
by a number of authors as the Lower Bajocian species which has been well figured by 
Benecke (1905 : 162, pi. n, figs. 1-3) under its correct name Gryphaea ferruginea 
(Terquem). Both forms lie on the border-line between Liostrea and Gryphaea, the 
right valve being almost flat and the left valve feebly convex. 

The specimens now recorded are subquadrate to suborbicular in outline and the 
largest was originally about 70 mm. high. Their general shape is, therefore, rather 
similar to that of the shell figured by de Loriol in 1881 as Ostrea roemeri. They are 
broader than Roemer's figure upon which this latter species was founded and Quen- 
stedt's fig. 22, but in the upper valve of the better preserved specimen (fig. yb) the 
beak is directed posteriorly in much the same manner as in the figures of these 
authors. This specimen has a relatively large attachment area whereas that of the 
specimens figured by previous authors is small. 

The type specimen of L. polymorpha came from the Upper Jurassic (probably 
Lower Kimmeridgian) of Streitberg, in Franconia. Of the oysters from Cutch, India, 
described by the present writer (Cox 1952), "Gryphaea sp. indet." (pi. 9, figs, ^a-c) 
from the Upper Oxfordian seems very close to the specimens now described and 
could belong to L. polymorpha. 

Subgenus CATINULA Rollier 191 1 

Liostrea (Catinula) alimena (d'Orbigny) 
PL 9, figs. 6a, b 

18406. Exogyra conica J. de C. Sowerby, pi. 22, fig. 27 (non J. Sowerby sp.). 

1850. Ostrea alimena d'Orbigny : 343. 

19346. Ostrea (" Catinula ") alimena d'Orbigny ; Arkell : 34, pi. 5, figs. 1-15. 

1952. Liostrea (Catinula) alimena (d'Orbigny) ; Cox : 76, pi. 6, figs. 7-10. 

i960. Ostrea (Catinula) cf. ancliffensis Cox & Arkell ; Joubert, pi. 8, fig. 8. 

Material. Several specimens. 

Localities and horizons. 3^ miles W. of Melka Biini, also 11 miles W. of 



FROM TANGANYIKA AND KENYA 73 

Rahmu, N.E. Kenya ; Callovian, Rukesa Shales. Kulong, 2 miles S.W. of Muddo 
Erri, also top of hills S. of Rahmu-Melka Murri road, 10 miles W. of Rahmu, N.E. 
Kenya ; Callovian [?-Lower Oxfordian], Muddo Erri Limestones. Magindu, 
Central Railway, and 2 km. to the east, Tanganyika ; Callovian. 

Remarks. The specimens now recorded fall within the range of variation of L. 
alimena as described (Cox 1952) from the Callovian and Oxfordian of Cutch, India. 
It is difficult to define any difference between this species and L. ancliffensis Cox & 
Arkell (1948 : 20), from the Bathonian, so far as the general form of the shell is 
concerned, but L. ancliffensis does not exceed 11 mm. in height whereas L. alimena 
commonly attains a much larger size. Certainly the numerous small specimens in 
an oyster bed of which a fragment was figured by Joubert (i960) could not be sepa- 
rated from L. ancliffensis, but other specimens from the same formation (the Rukesa 
Shales) are larger. The radial ribs present in many English specimens referred to 
this species and described by Arkell (1934&) have not been observed in specimens 
from Cutch or from East Africa. 

Genus GRYPHAEA Lamarck 1801 

Gryphaea hennigi Dietrich 
PI. 11, figs, ia, b 

1900. Gryphaea lobata Cjuenstedt ; Miiller : 521, pi. 16, figs. 6, 6a. 

1925. Gryphaea hennigi Dietrich : 6, pi. 2, fig. 4. 

1952. Gryphaea hennigi Dietrich ; Cox : 83, pi. 8, figs. 7(F), 8, ga-c. 

Material. Three left valves (nos. LL. 16848-50). 

Locality and horizon. Look-out hill opposite Kingura village, north of Wami 
river, Tanganyika ; Upper Oxfordian. 

Remarks. The most notable feature of these specimens is the protruding lobe- 
like antero-ventral region, and in one specimen the growth-rugae show that this was 
separated from the rest of the valve by a broad sinus of the ventral margin. The 
specimens are broken away posteriorly, but the largest appears from the growth- 
rugae to have had a rather similar postero-ventral lobe. They appear to belong to 
Gryphaea hennigi, which, according to Aitken (1961 : 25) is abundant in the Lower 
Kimmeridgian Septarian Marl of the Mandawa-Mahokondo anticline. They are also 
extremely close to G. moondanensis Cox (1952 : 87, pi. 9, figs. 4, 7, 8), a species from 
the Tithonian of Cutch, north-western India, in which an antero-ventral lobe is a 
conspicuous feature. 

Genus EXOGYRA Say 1820 

Exogyra nana (J. Sowerby) 
Pi. 11, figs. 5, 6a, b 

1822a. Gryphaea nana J. Sowerby : 114, pi. 383, fig. 3. 

1872. Ostrea bruntrutana Thurmann ; de Loriol : 399, pi. 24, figs. 7-18. 

1929. Exogyra nana (J. Sowerby) ; Weir : 20, pi. 1, figs. 11-13. 



7t JURASSIC BIVALVIA AND GASTROPODA 

1930. Exogyra nana (J. Sowerby) ; Weir : 85, pi. 10, figs. 27-29. 
1052. Exogyra nana (J. Sowerby) ; Cox : 92, pi. 10, figs. 2-4. 

Material. Several specimens. 

Localities and horizons. Ogar Wein and Tifo, N.E. Kenya ; Oxfordian, 
Golberobe Beds. z\ miles S.W. of Rahmu, N.E. Kenya ; Oxfordian, Rahmu Shales. 
Hereri river crossing, 3 miles S. of Melka Kunha, N.E. Kenya ; Kimmeridgian, 
Hereri Shales. Kiwate-Mkange track, 5 miles S.S.E. of Mkange, Bagamoyo hinter- 
land, Tanganyika ; Oxfordian or Kimmeridgian. Kindope valley, near Tendaguru, 
Tanganyika ; Upper Kimmeridgian, Nerinella Bed. 

Remarks. Most of the specimens are irregular in form, but some from the Rahmu 
Shales are characterized by their regularly lunate outline, recalling that of the larger 
form E. foitrtaiti Stefanini (see Cox 1935a : 174, pi. 17, figs. 14a, b). Occasional 
European specimens of E. nana (e.g. de Loriol 1872, pi. 24, figs. 12, 12a, b) are, how- 
ever, similar in shape. 



Superfamily TRIGONIACEA 

Family TRIGONIIDAE Lamarck 1819 

Genus TRIGONIA Bruguiere 1789 

Trigonia costata Parkinson 
PL 11, figs. 2a, b 

1811. Trigonia costata Parkinson : 175, pi. 12, fig. 4. 

1875. Trigonia costata Sowerby ; Lycett : 147, pi. 29, figs. 5-10. 

1932. Lvriodon costatum (Sowerby) ; Lebkiichner : 101, pi. 15, fig. 9 ; pi. 16, fig. 3. 

Material. One specimen (no. LL.35104), ex B.P. Coll. 

Locality and horizon. Magole, 5 miles N.W. of Kidugallo, Tanganyika ; 
Bajocian. 

Remarks. This small specimen, about 18 mm. long and 16 mm. high, appears 
to be referable to the true T. costata, a Bajocian species which has been much mis- 
interpreted. The angular concentric ribs, 16 in number, almost touch the marginal 
carina in the right valve, but are separated from it in the left by an ante-carinal 
depression which is fairly narrow, although broader than in the new species T. kenti, 
described below. The posterior area bears a relatively prominent nodose rib the 
position of which is anterior to median. Between this rib and the marginal carina 
is a single nodose thread and on its posterior side are three other threads, irregularly 
arranged. The escutcheon has a few transverse wrinkles. These features are similar 
to those of English specimens of T. costata which have reached the same stage of 
growth. Previous records of T. costata from East Africa are from post-Bajocian 
beds and are to be rejected. 



FROM TANGANYIKA AND KENYA 75 

Trigonia kidugalloensis sp. nov. 
PL 11, figs. 3<z, b, c 

Holotype and paratype. Holotype, no. LL.35105 ; one paratype, no. LL. 
35106. Both ex B.P. Coll. 

Diagnosis. Small (length of holotype, when complete, c. 17 mm.), rather 
strongly inflated, length and height nearly equal, umbones not prominent ; curva- 
ture of marginal carina very feeble ; posterior area moderately broad, concave 
transversely and forming a relatively wide angle with the flank ; ventral margin 
apparently evenly convex. Flank ornamented with relatively narrow and numer- 
ous, evenly curved, round-topped concentric ribs separated by intervals of about 
the same width ; number of ribs on each valve of holotype 27. Ribs end a short 
distance from the prominent, serrated marginal carina, which is thus bordered by an 
ante-carinal groove, slightly wider in left valve than in right. The area has no 
marked median carina or groove, but bears 6-7 nodose radial threads, and the es- 
cutcheon carina is also nodose. 

Locality and horizon, i^ miles N.N.W. of Kidugallo, Tanganyika ; Bajocian. 

Remarks. This form resembles the European Bajocian species T. hemisphaerica 
Lycett (re-described Lycett 1877 : 174, pi. 31, figs. 4-8 ; pi. 33, figs. 4-6 (var. gre- 
garia)) in the closeness of the spacing of its concentric ribs, but it is less elongate and 
more strongly inflated, and has a more distinct ante-carinal groove, especially on the 
left valve. The broader ante-carinal groove and less prominent umbo distinguish 
the new species from T. hemisphaerica race asiatica Douville (1916 : 29, pi. 4, fig. 9), 
from the Bajocian of Sinai. In the French Bajocian species T. gadoisi Cossmann 
(1912 : 8, pi. 1, figs. 6-8) the concentric ribs are still more closely arranged. 

Trigonia kenti sp. nov. 
PI. 11, figs. 4a, b, c 

Specific name. After Dr. P. E. Kent, of the British Petroleum Company, 
Limited. 

Holotype and paratype. Holotvpe, no. LL. 35107 ; one paratype, no. LL. 
35108. Both ex B.P. Coll. 

Diagnosis. Small (length of holotype 22 mm.), moderately inflated, length 
slightly exceeding height, umbones moderately prominent and acute ; ventral 
margin tending to be subangular in middle and slightly sinuate posteriorly ; posterior 
area rather narrow, forming relatively low angle with flank. Flank ornamented 
with rather angular concentric ribs which are curved irregularly in places and are 
moderately wide-spaced (about 2 mm. apart) until a relatively late growth-stage, but 
become crowded together near ventral margin. The ribs extend in both valves al- 
most to the sharp and not strongly nodose marginal carina, the ante-carinal depres- 
sion being very narrow. Posterior area feebly convex, with a median rib which is most 
conspicuous in earlier stages of growth and with about four very irregularly spaced 



76 JURASSIC BIVALVIA AND GASTROPODA 

radial threads. Escutcheon carina apparently weakly serrated (but eroded in 
available specimens). 

Locality and horizon. 6 miles N.W. of Kidugallo, Tanganyika ; Bajocian. 

Remarks. The crowding together of the concentric ribs near the ventral margin 
suggests that the two specimens studied, although small, are full-grown representa- 
tives of their species. This feature, the irregular curvature of the ribs in places, and 
the very narrow ante-carinal depression distinguish this species from T. costata 
Parkinson. 

Trigonia cf. brevicostata Kitchin 
PI. ii, fig. 7 

1903. Cf. Trigonia brevicostata Kitchin : 23, pi. 2, figs. 4, 5. 

J 939- Cf. Trigonia brevicostata Kitchin ; Stefanini : 224, pi. 24, figs. 11, 12. 

1952. Cf. Trigonia brevicostata Kitchin ; Cox : 112. 

Material. Four imperfect specimens. 

Locality and horizon, i mile N. of Asaharbito, N.E. Kenya ; Bathonian [? or 
Callovian], Asaharbito Beds. 

Remarks. The specimens are internal and external moulds of the original shells, 
the largest of which was originally almost 30 mm. long although the others are much 
smaller. The ornament consists of well separated, coarse concentric ribs which 
swing down to some extent and swell out at their posterior end ; they are separated 
from the marginal carina by a well-marked ante-carinal depression, which appears to 
be a little wider in the left valve than in the right. The posterior area bears relative- 
ly coarse radial threads. These specimens differ from typical examples of T. brevi- 
costata in their slightly coarser ribbing (possibly due to their state of preservation) 
and in the tendency of the ribs to swing down posteriorly, but it is quite possible that 
they belong to that species. T. brevicostata occurs typically in the Callovian of Cutch, 
India, and has been recorded by Stefanini from beds in southern Somalia which seem 
to be approximately Callovian in age. 

Trigonia elongata J. de C. Sowerby 
PI. 11, fig. 8 

1823a. Trigonia elongata J. de C. Sowerby : 39, pi. 431. 

1903. Trigonia chariensis Kitchin : 18, pi. 1, fig. 4 ; pi. 2, fig. 1. 

1952. Trigonia elongata Sowerby ; Cox : 109, pi. 12, figs. 3, 4, 7. 

Material. One specimen (no. LL. 35109), ex B.P. Coll. 

Locality and horizon. About i\ miles W. of Mandawa, Tanganyika ; Callo- 
vian (?). 

Remarks. This specimen does not seem distinguishable from English examples 
of T. elongata, a species discussed by the present writer in the above-cited work, in 
which specimens from the Callovian of Cutch, India, are described. In England its 
range extends from the Bathonian to the Oxfordian. 



FROM TANGANYIKA AND KENYA 77 

Trigonia migeodi sp. nov. 
PI. 11, figs. 11a, b 

Specific name. After the late F. W. H. Migeod, for some years leader of the 
British Museum East Africa Expedition. 

Diagnosis. Small (length of holotype 17-5 mm.), moderately inflated, length 
well in excess of height, umbones moderately prominent, marginal carina well 
curved ; posterior area broad ; ventral margin rather feebly convex, almost straight 
towards its posterior end. Flank ornamented with relatively narrow and numerous, 
round-topped concentric ribs separated by intervals of almost the same width ; 
number on each valve of holotype estimated at about 30 (those on umbonal region 
worn away). Ribs almost reach carina on right valve. The posterior area has a 
median groove and bears about 6 radial threads on its antero-ventral side and 
probably about the same on its postero-dorsal side, where, however, they are not 
well seen. 

Holotype. No. L.51193, a right valve. The only specimen. 

Locality and horizon, i mile N.W. of Tendaguru hill, Tanganyika ; Upper 
Kimmeridgian, Nerinella Bed. 

Remarks. This specimen differs from T. kidugalloensis in its more elongate out- 
line, its more strongly curved marginal carina, and its more closely spaced ribs. It 
is quite close to the European Bajocian species T. hemisphaerica Lycett but has more 
closely spaced ribs. It also much resembles T. tenuis Kitchin (1903 : 35, pi. 3, 
figs. 5, 6), from the Upper Jurassic of India (re-named T. oomia by Strand 1928 : 72), 
but it has more closely spaced ribs and a more conspicuous median groove on its 
posterior area. 

Trigonia dainellii Venzo 
PL 11, fig. 9 

1945. Trigonia (Lyriodon) dainellii Venzo : 15, figs. la-c. 

1949. Trigonia [Lyriodon) dainellii Venzo ; Venzo : 138, pi. 2, figs. 1-5. 

1949. Trigonia [Lyriodon) brevicostata Kitchin ; Venzo : 137, pi. 1, figs. 34, 35. 

i960. Trigonia sp. nov. [brevicostata Venzo non Kitchin) ; Joubert, pi. 7, figs. \a, b. 

Material. Several specimens. 

Localities and horizon. Odda, and W. slope of hill \ mile E. of Hafura, both 
N.E. Kenya ; Uppermost Jurassic or basal Cretaceous, Danissa Beds. 

Remarks. The general form and the flank ornament of this species are those of a 
typical costate Trigonia, but there is a tendency for the ribs to undulate irregularly 
in later stages of growth. A peculiar feature of the specimens now recorded is that 
the ribs of the flank are continued across the marginal carina, some of them bifurcat- 
ing at the same time. There is a shallow, linear ante-carinal groove. The posterior 
area bears two or three strong radial ribs, and in later stages of growth these are 
crossed by transverse ridges. 



78 JURASSIC BIVALVIA AND GASTROPODA 

The large series of specimens figured by Venzo (1949) as T. brevicostata Kitchin 
and as varieties of his new species T. dainellii seem to present all gradations between 
shells in which the flank ribs continue on to the carina, as in the specimens now 
recorded, and shells with a smooth ante-carinal area ; this area varies in width and 
does not always have a well-defined anterior border. In some specimens included 
by Yenzo in the forma typica of T. dainellii (e.g. his fig. 3) some of the ribs bifurcate 
on the carina, as in the present specimens. 

T. dainellii bears a very close resemblance to the European species which has been 
well figured by de Loriol (1868 : 160, pi. 10, figs. 12-16 ; pi. 11, fig. 3) under the 
name T. truncata Agassiz. The species in question has a wide range of variation 
similar to that of T. dainellii, and some of its variants have been considered by 
Munier-Chalmas (1882 : 498-500) to belong to distinct species to which he has as- 
signed names. The specimens from Kenya now recorded are close to de Loriol's pi. 
10, figs. 12, 14, re-named by Munier-Chalmas T. autissiodorensis and T. breoni 
respectively. The type-specimens of both of these " species " are from the " Port- 
landian " (probably Upper Kimmeridgian in the British sense) of Auxerre, Yonne, 
France. It is possible and even probable that T. dainellii is synonymous with these 
European forms, although perhaps not with the true T. truncata, a species founded by 
Agassiz on ill-preserved specimens. 

Subgenus FRENGUELLIELLA Leanza 1942 

Trigonia (Frenguelliella) tealei Cox 

PI. 11, fig. 10 
19376. Trigonia tealei Cox : 201, pi. 16, figs. 2, 3. 

Material. Several specimens, including the holotype (no. L. 541 13). 

Localities and horizons. S. of Tarawanda, 11 miles S.E. of Lugoba, Tangan- 
yika (type-locality) ; Callovian. 2 miles E. of Magindu Station, Central Railway, 
Tanganyika ; Callovian. Chinamba, f mile S. of Amboni quarries, Tanga, Tangan- 
yika ; Callovian? (ex B.P. Coll.). Scarp face, eastern margin of Makoko plain, 
Bagamoyo hinterland, Tanganyika, also Usigiwa river, 6 miles W.S.W. of Kiwanga, 
Bagamoyo hinterland ; Oxfordian. 

Remarks. The flank ornament of this species resembles that of T. brevicostata 
Kitchin (1903 : 23, pi. 2, figs. 4, 5), from the Callovian of Cutch, India, but the orna- 
ment of the posterior area, radial in T. brevicostata and transverse in T. tealei, en- 
ables the two forms to be distinguished. 

Subgenus INDOTRIGONIA Dietrich 1933 

Trigonia (Indotrigonia) smeei auct. 

1914. Trigonia smeei Sowerby ; L,ange : 225, pi. 20, figs. 8-13 ; pi. 21, figs. 1-7. 
1933. Trigonia (Indotrigonia) smeei Sowerby ; Dietrich : 30, pi. 3, figs. 48-51, 54-56. 



FROM TANGANYIKA AND KENYA 79 

Material. Very numerous specimens. 

Localities and horizon. Many localities around Tendaguru, Tanganyika ; 
Upper Kimmeridgian. 

Remarks. The trigoniids of the T. smeei group occurring in Tanganyika have 
recently been treated exhaustively by Aitken (1961), who considers that they belong 
to at least five species, none identical with the true T. smeei, which occurs in the 
Upper Oxfordian of Cutch, India. The name T. (Indotrigonia) africana is assigned 
by him (1961 : 75, pi. 8, figs. 2-7 ; pi. 9, figs. 1, 2) to the form most commonly found 
at Tendaguru. 

Trigonia {Indotrigonia) dietrichi Lange 

1914. Trigonia dietrichi Lange : 233, pi. 20, fig. 7. 

1933. Trigonia (Indotrigonia) dietrichi Lange ; Dietrich : 32, pi. 2, figs. 38-41. 

Material. Two specimens (nos. L. 52640, L. 52664). 

Locality and horizon. Kindope valley, near Tendaguru, Tanganyika ; Upper 
Kimmeridgian, " Trigonia smeei " Bed. 

Remarks. These specimens, which are imperfect, agree with T. dietrichi as 
figured by Dietrich, and show the strong upward bend of the costae as they approach 
the marginal carina. This is not a feature indicated in Lange's original figure, but 
his description refers to a slight upward bend of the costae. 

Genus MYOPHORELLA Bayle 1878 

Myophorella quennelli sp. nov. 
PI. 12, figs, la, b 

Specific name. After Mr. A. M. Quennell, formerly Director of the Tanganyika 
Geological Survey, collector of the type specimens. 

Diagnosis. Of small-medium size (original length of paratype, the larger speci- 
men, c. 30 mm.), length only slightly in excess of height ; umbo moderately pro- 
minent ; anterior and ventral margins forming a broad curve. Marginal carina 
strongly curved ; posterior area broad, forming a wide angle with the flank, and with 
an almost vertical posterior margin. Flank ornamented with feebly curved, weakly 
tuberculate costae which extend to the marginal carina and slope steeply down from 
it except in the earlier growth-stages, where they are concentric about the umbo. 
The intervals are about twice the width of the costae except in the posterior corner of 
the flank, where they are narrower. Two short costae, seen in the holotype but 
obscured in the paratype, occupy the space near the anterior margin corresponding 
to the change in the curvature of the main costae. Area without sulcus or radial 
ribs, but crossed by closely and evenly arranged ridges parallel with posterior 
margin. 

Holotype and paratype. Holotype, no. LL.11809 ; one paratype, no. LL.11810. 
Both are left valves. 



8o JURASSIC BIVALVIA AND GASTROPODA 

Locality and horizon. Just W. of Mabokweni, 4 miles N.W. of Tanga, Tangan- 
yika ; Kimmeridgian. 

Remarks. There is no described Myophorella with which this species could be 
confused. In M. kutchensis (Kitchin) (1903 : 84, pi. 8, figs. 7-9) the umbo is less 
prominent and the costae are broken up into irregularly distributed tubercles on the 
anterior part of the flank. 

Myophorella kiwawaensis sp. no v. 
PL 12, figs. 2a, b 

Diagnosis. Small, ovate, almost orbicular, length (c. 16 mm.) only slightly 
exceeding height. Umbones not prominent, at anterior third of length. Anterior 
and ventral margins forming an even curve of strong convexity ; posterior margin 
relatively long, erect. Marginal carina gently curved, obtusely angular, nodose ; 
escutcheon carina nodose. Posterior area short, moderately broad, without median 
groove, and bearing closely arranged transverse threads. Flank with rather deli- 
cate nodose costae, those near posterior end straight and vertical, middle ones well 
curved. 

Holotype and paratypes. Holotype, no. LL.35110, also three paratypes, 
including no. LL.35111 ; all ex B.P. Coll. 

Locality and horizon. Kiwawa stream, 2400 yards S.E. of Mitekera survey 
beacon, northern Mandawa area, Tanganyika ; Upper Kimmeridgian. 

Remarks. The absence of a radial groove on the posterior area distinguishes this 
species from young specimens of Myophorella striata (Miller) and of related Inferior 
Oolite species. 

Genus LAEVITRIGONIA Lebkiichner 1932 

Laevitrigonia dwanikana sp. nov. 
PL 12, fig. 5 

Diagnosis. Shell of medium size (length 35 mm.), ovate, rounded posteriorly ; 
length not greatly exceeding height. Umbo not prominent, situated at about 
anterior third of length ; ventral margin strongly and symmetrically convex. 
Marginal carina an obscure ridge ; posterior area convex, forming a wide angle with 
the flank ; no ante-carinal depression. Anterior part of flank ornamented with 
broad, depressed rounded ribs, some split up into irregular nodes by transverse 
furrows, separated by much narrower intervals. In earlier stages of growth the 
ribs bend up to the marginal carina, but in later stages they end half-way to the 
carina, leaving the rest of the flank smooth. Posterior area apparently without 
ornament (but rather eroded in holotype). 

Holotype. No. L. 52692 ; the only specimen. 

Locality and horizon. Dwanika river, Tendaguru, Tanganyika ; Upper 
Kimmeridgian, " Trigonia smeei " Bed. 



FROM TANGANYIKA AND KENYA 81 

Remarks. This is a very typical Laevitrigonia, differing from the type-species, 
L. gibbosa (J. Sowerby), in the absence of an ante-carinal depression, but comparable 
to some other species from the Upper Jurassic of Europe, for example, L. acteon 
(Munier-Chalmas) (1882 : 503, pi. 12, fig. 5) and L. oustaleti (Munier-Chalmas) (1882 : 
503, pi. 12, fig. 7). It differs from previously known species in details of ornament. 

Genus RUTITRIGONIA Van Hoepen 1929 

Rutitrigonia stefaninii (Venzo) 

PL 12, figs. 3a, b 

1942a. Trigonia (Laevitrigonia) stefaninii Venzo : 27, fig. 10. 

1949. Trigonia (Laevitrigonia) stefaninii Venzo ; Venzo : 145, pi. 2, figs. 28-33 ; also figs. 

34-50 (varieties). 
i960. Trigonia stefaninii Venzo ; Joubert, pi. 7, figs. 2a, b. 

Material. Two specimens (nos. L. 92180, L. 92273). 

Localities and horizon. 3 miles N.E. of Melka Dakacha, N.E. Kenya, and 2 
miles S. of Melka Dakacha ; Upper Kimmeridgian, Dakacha Limestones. 

Remarks. The better preserved specimen, now figured, is a trigonally ovate 
shell in which the posterior carina fades away after an early stage of growth and the 
weak, undulating ribs are confined to the anterior end of the flank. It is closely com- 
parable to some of Venzo's figures. This is obviously a variable species and the 
numerous varietal names introduced by Venzo seem unnecessary. 

This species is of some interest as it appears to belong to the genus Rutitrigonia, 
hitherto known only from Cretaceous rocks. Its umbo is rather more prominent 
than in the more typical representatives of the genus, but the fading away of its 
narrow, undulating flank costae on the posterior part of the flank, its smooth poste- 
rior area, and its ill-defined marginal carina are exactly as in such species as R. 
excentrica (Parkinson) (figured Lycett, 1875 : 94, pi. 20, figs. 5, 6 ; pi. 21, figs. 6, 7 ; 
pi. 22, figs. 5, 5«) and R. laeviuscula (Lycett) (1875 : 96, pi. 22, fig. 6). 

Genus OPISTHOTRIGONIA Cox 1952 

Opisthotrigonia carta (Aitken) 
PI. 12, fig. 4 
1 961. Laevitrigonia curta Aitken : 97, pi. 14, figs. 1-3. 

Material. Two specimens (including no. LL.35112), ex B.P. Coll. 

Locality and horizon. Mpilepile stream, 800 yards E.N.E. of junction of main 
road and Mahokondo road, Mitole, northern Mandawa area, Tanganyika ; Upper 
Kimmeridgian. 

Remarks. Prior to the publication of Aitken's paper, these specimens had been 
described in MS. as a new species of Opisthotrigonia. One which is 43 mm. long and 
considerably larger than any of Aitken's specimens is here figured to illustrate the 



82 JURASSIC BIVALVIA AND GASTROPODA 

relative size of the depressed ante-carinal space in the right valve. Except in very 
early growth stages the rather irregular ribs cross this space and terminate at or very 
close to the blunt marginal carina. The species appears to be more closely related 
to the typical species of Opisthotrigonia than to Laevitrigonia. 



Superfamily MODIOMORPHACEA 

Family HIPPOPODIIDAE nov. 

Genus HIPPOPODIUM J. Sowerby 1819 

Hippopodium quenstedti (Dietrich) 

1933. Epihippopodium quenstedti Dietrich : 71, pi. 9, fig. 136 ; pi. 10, figs. 142, 143. 

Material. Six specimens. 

Localities and horizons, i mile N.W. of Tendaguru hill, Tanganyika ; Upper 
Kimmeridgian, Nerinella Bed. Kindope road, Tingutitinguti creek, and i\ miles 
N.N.W. of Tapaira, all near Tendaguru, Tanganyika ; Upper Kimmeridgian, 
" Trigonia smeei " Bed. 

Remarks. Although Dietrich founded a genus Epihippopodium on this species, 
comparison of his figures showing the internal characters of the shell and of the 
present specimens with examples of Hippopodium ponderosum J. Sowerby, the 
Lower Liassic type-species of Hippopodium, shows such close agreement in all 
essential characters that the generic separation of the Tendaguru form seems un- 
justified. H. quenstedti differs from H. ponderosum only in its larger size and its 
broader form. It would thus seem that Hippopodium lingered on in some remote 
area after its disappearance from N.W. Europe at the close of the Middle Lias, to re- 
appear almost at the top of the Jurassic in East Africa. 

Superfamily CRASSATELLACEA 

Family ASTARTIDAE d'Orbigny 1844 

Genus AST ARTE J. Sowerby 1816 

Astarte lurida J. Sowerby 
PI. 12, fig. 8 



1816a. Astarte lurida J. Sowerby : 81, pi. 137, fig. 1. 

1836. Astarte subtetragona Miinster [previously nom. nud.] ; Roemer : 113. 

Astarte excavata Sow. ; Goldfuss : 190, pi. 134, figs. 6c, d (non a, b) (non J. Sowerby). 

Astarte subcarinata Miinster in Goldfuss : 190, pi. 134, figs, ja, b. 



1837 
1837 
1840 
1842 

1853 
1869 
1874 



Astarte subtetragona Miinster 
Astarte subtetragona Miinster 
Astarte subtetragona Miinster 
Astarte subtetragona Miinster 
Astarte subtetragona Miinster 



Goldfuss : 304 (Verbesserung, for pi. 134, figs. 6c, d.). 

Roemer : 13. 

Chapuis & Dewalque : 150, pi. 22, fig. 4. 

Brauns : 226. 

Dumortier : 176, pi. 40, figs. 5, 6. 



FROM TANGANYIKA AND KENYA 83 

1874. ?Astarte lurida Sow. ; Dumortier : 175, pi. 40, figs. 2-4. 
1905. Astarte elegans Sow. ; Benecke : 214, pi. 16, figs. 1-3 (non J. Sowerby). 
1923. Astarte sublaevis d'Orbigny ; Ernst : 67, pi. 1, figs. 13a, b only (non d'Orbigny). 
1935. Astarte subtetragona Miinster (with vars. brevis, krumbecki and subcarinata) ; Kuhn : 
123, pi. 8, figs. 39a, b ; pi. 9, figs. 17a, b, 10a, b, 28a, b ; pi. 10, figs. 20a, b. 

Material. One specimen (no. LL. 35044). 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. Sowerby's holotype of Astarte lurida (B.M. (N.H.) no. 43082), from 
the neighbourhood of Naunton, Gloucestershire, belongs to a widely distributed 
Upper Liassic species. Abundant specimens from the Cotswold Cephalopod Bed 
(Yeovilian) illustrate the variability of the species. There is complete intergrada- 
tion between ovate shells in which the umbo is not terminal and the postero-dorsal 
and posterior margins meet in a broad curve, and shells with a rectangular to rhom- 
boidal outline in which the umbo is terminal and the margins mentioned meet in a 
well-defined right or obtuse angle. There is also considerable variation in ornament, 
some specimens having fairly regular concentric ribs and others irregular rugae. 
These observations have led to the conclusion that A. subtetragona, based on rhom- 
boidal specimens, should be regarded as a synonym of A. lurida. 

The specimen now recorded is 38-5 mm. long and thus of about the same size as 
many specimens from the Cotswold Cephalopod Bed. Like the holotype, it is a 
relatively ovate representative of the species. In England this species ranges from 
the bifrons Zone of the Whitbian stage of the Upper Lias to the scissum Zone, near 
the base of the Inferior Oolite. 

Astarte pulfreyi sp. nov. 
PI. 12, figs. 12a, b, 13 

Specific name. After Dr. W. Pulfrey, lately Director of the Kenya Mines and 
Geological Department. 

Diagnosis. Of large-medium size (length of largest specimen c. 33 mm.), sub- 
orbicular with a quadrate tendency, length very slightly exceeding height, moderately 
inequilateral ; inflation weak. Umbones at about anterior third of length, not 
incurved, directed anteriorly, their outline continuous with postero-dorsal outline, 
which is feebly convex and gently inclined, joining the feebly convex, sub vertical 
posterior margin in an even curve or forming a rounded-off, obtuse angle with it ; 
antero-dorsal outline feebly concave near umbo, steeply sloping ; anterior margin 
rather strongly convex ; ventral margin strongly convex anteriorly, less convex 
posteriorly, where it forms a rounded-off, obtuse angle with posterior margin. 
Escutcheon and lunule narrow and shallow, almost absent. No ornament except 
growth-rugae. Valve-margins denticulate internally. 

Holotype and paratypes. Holotype, no. LL. 35027 ; 4 paratypes. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 



84 JURASSIC BIVALVIA AND GASTROPODA 

Remarks. The hinge-teeth are not seen in any of the specimens but there is 
little doubt that the species is an Astarte. It is more quadrate in outline and less 
strongly inequilateral than A. lurida, recorded above. A. camertonensis Moore 
(1867 : 213, pi. 7, fig. 21), from the Pliensbachian of England, is more elongate. 



Astarte didimtuensis sp. nov. 
PL 12, figs. 10a, b, c, 11a, b, c 

Diagnosis. Small (length of largest specimen c. 12-5 mm.), ovate, inequilateral ; 
height three-quarters to four-fifths of length, beaks from anterior fifth to quarter of 
length ; inflation moderate. Umbones subangular, not incurved, prosogyrous ; 
postero-dorsal outline straight, subhorizontal, meeting the strongly convex posterior 
margin in an even curve which is continued by the strongly convex ventral and 
anterior margins ; antero-dorsal outline strongly concave. Lunule moderately 
impressed ; escutcheon narrow and shallow. Ornament consisting of fine, equal 
concentric riblets which may show slight irregular undulations on posterior part of 
surface. 

Holotype and paratypes. Holotype, no. LL.35032 ; 9 paratypes. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. Astarte didimtuensis is more elongate and has finer concentric orna- 
ment than its associated species A . subminima, described below. It is quite unlike 
A. voltzii Roemer (1836 : 112, pi. 7, fig. 17), the common small astartid of the 
European Upper Lias, differing in its more elongate and much more compressed 
form and in the even distribution and fineness of its concentric threads. 



Astarte subminima sp. nov. 
PL 12, figs. 14a, b 

Diagnosis. Small (length c. 6 mm.), subtrigonal with an orbicular tendency, 
inequilateral ; height and length almost equal ; beak at about anterior quarter of 
length ; inflation weak. Umbo sharply rounded in outline, not incurved, slightly 
prosogyrous ; postero-dorsal outline slightly convex, gently sloping, forming a well- 
marked, obtuse angle with the rather low, straight, subvertical posterior margin ; 
ventral margin strongly convex, meeting posterior margin in an ill-defined, obtuse 
angle ; anterior margin low ; antero-dorsal outline concave, steep. Lunule 
moderately impressed, no escutcheon. Ornament consisting of fine, equal con- 
centric ribs. Ventral margin denticulate internally. 

Holotype. No. LL. 35042. The only specimen. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This species is rather similar to Astarte minima Phillips, from the 



FROM TANGANYIKA AND KENYA 85 

Bajocian of Europe, but is more finely ribbed and less rectangular in outline. A. 
depressa Goldfuss, a Bajocian species well figured by Cossmann (1913a : 9, pi. 3, 
figs. 18-27), is more trigonal in outline. A. gillieroni Mayer (1875 : 234, pi. 10, 
fig. 4), Upper Lias of Switzerland, is a larger form with a more strongly prosogyrous 
umbo. 

Astarte sp. 

PL 12, figs. 15a, b 

Material. One specimen (no. LL. 35043), defective postero-ventrally. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Description. Small (length when complete c. 7-5 mm.), suborbicular, with a tri- 
gonal tendency, inequilateral ; height and length almost equal, beaks at anterior 
fifth of length ; inflation moderately strong. Umbo rather broadly rounded, well 
incurved ; postero-dorsal outline moderately convex and sloping, forming a rounded- 
off, obtuse angle with the low, almost straight, subvertical posterior margin ; ventral 
margin rather strongly convex ; antero-dorsal outline very feebly concave, steeply 
sloping ; anterior margin low. Lunule (rather obscured in this single specimen) 
moderately impressed ; presence of escutcheon doubtful. Ornament consisting of 
fine, equal concentric riblets. 

Remarks. This form is more gibbose than A. subminima and has rather stronger 
concentric riblets, but the single specimen seems too imperfect to serve as the type 
of a new species. 

Astarte kenti sp. nov. 
PL 12, figs. 6a, b, ya, b 

Specific name. After Dr. P. E. Kent, of the British Petroleum Co., Ltd. 

Diagnosis. Small (maximum length c. 15 mm.), trigonally ovate, height two- 
thirds to three-quarters of length ; inequilateral, beaks from anterior quarter to 
third of length ; inflation weak. Umbones obtusely angular, not incurved, mode- 
rately prominent ; postero-dorsal outline convex, gently sloping, antero-dorsal 
outline almost straight, steeply sloping ; lunule absent or ill-defined ; escutcheon, if 
distinguishable, narrow and limited by ill-defined umbonal ridges. Posterior margin 
feebly convex, varying in height and inclination ; ventral margin flat to feebly con- 
vex. Early growth-stages ornamented with regular, close-spaced concentric ridges, 
later stages with rather irregular concentric undulations and rugae. Valve margins 
denticulate internally. 

Holotype and paratypes. Holotype, no. LL.35113 ; about 18 paratypes. 

Locality and horizon. Near site of Mandawa well no. 1, Tanganyika ; Bajo- 
cian^). 

Remarks. The most closely described Bajocian species is Astarte hauthali Wetzel 
(1911 : 249, pi. 20, figs. 19, 20), which is slightly more rectangular. 



86 JURASSIC BIVALVIA AND GASTROPODA 

Astarte pindiroensis sp. nov. 

PL 13, figs. 4a, b, 5«, b 

Diagnosis. Small (length of holotype 5-5 mm ; of largest paratype 11 mm.), 
rectangularly ovate, height from four-fifths to five-sixths of length, inflation mode- 
rate. Inequilateral, umbones situated from anterior quarter to third of length, 
scarcely incurved, directed anteriorly, their outline continuous with the feebly con- 
vex, gently sloping to sub-horizontal postero-dorsal outline of the shell, which merges 
in a broad curve with the feebly convex, only slightly oblique posterior margin ; 
ventral margin moderately convex, forming a rounded-off, obtuse angle with poste- 
rior margin and merging in an even curve with the broadly convex anterior margin ; 
concavity of antero-dorsal outline confined to neighbourhood of beak. No diagonal 
ridge. Escutcheon very narrow, bordered by blunt umbonal ridges ; lunule an un- 
impressed cordiform area limited by faint striae. Ornament consisting of fine con- 
centric threads, slightly unequal and irregularly arranged in places. 

Holotype and paratypes. Holotype, no. LL.35206, figured paratype, no. 
LL. 35207, both extracted from a piece of limestone containing a large number of 
other paratypes. 

Locality and horizon. Tributary of Namakumbira stream, 1 mile S.E. of 
Nkomore, Mandawa-Mahokondo area, Tanganyika ; Bajocian (?), Pindiro Shales. 

Remarks. This species is smaller and less trigonal than A . kenti, described above. 
Its very fine ornament distinguishes it from the European Bajocian form A. minima 
Phillips. 



Astarte ayersi sp. nov. 
PI. 13, figs, ya, b 



Specific name. After Mr. F. M. Ayers, of the Kenya Geological Survey. 

Diagnosis. Rather small (length of holotype 15 mm.), triangularly subovate, 
slightly longer than high, evenly and fairly strongly inflated. Umbo prominent, 
narrowly rounded in outline, placed at about anterior third of length. Antero- 
dorsal outline slightly convex, sloping gently, and forming a rounded-off, obtuse 
angle with posterior margin ; posterior, ventral and anterior margins forming an 
even curve which is almost a semicircle : antero-dorsal outline strongly excavated. 
Ornament consisting of narrow, evenly spaced concentric ridges about 075 mm. 
apart in later growth-stages. 

Holotype and paratypes. Holotype, no. L. 83876 ; numerous paratypes, 
mainly imperfect. 

Locality and horizon, i mile N. of Asaharbito, N.E. Kenya ; Bathonian [? or 
Callovianl, Asaharbito Beds. 

Remarks. This species bears some resemblance to the European Bathonian 
species Astarte oolitharum Cossmann (1925 : 663, pi. 22, figs. 14, 15) (= A. depressa 
Morris & Lycett 1855, pi. 9, fig. 11, non Goldfuss), but is considerably larger. The 



FROM TANGANYIKA AND KENYA 87 

species Astarte daphne de Loriol (1891 : 244, pi. 26, figs. 25-27), Upper Oxfordian of 
Switzerland, is comparable in size and shape, but its concentric ribs are more closely 
spaced. 

Astarte muelleri Dacque 

1900. Astarte sp ; Miiller : 534, pi. 17, fig. 7. 
1910. Astarte mulleri Dacque : 31, pi. 4, fig. 5. 
19376. Astarte mulleri Dacque ; Cox : 202. 

Material. One specimen (no. L.54117). 

Localities and horizons. 2 miles E. of Magindu Station, Central Railway, 
Tanganyika ; Callovian. Miiller's original specimen came from a locality 1-5 km. 
W. of the Mahokondo stream, 24-5 km. N.W. of Kiswere, where the beds are now 
thought to be Callovian in age. 

Astarte aitkeni sp. nov. 
PL 12, figs. 9a, b, c 

Specific name. After Dr. W. G. Aitken, lately Director of the Geological Survey 
of Nyasaland, collector of the holotype. 

Diagnosis. Rather small (length of holotype 12 mm.), trigonally orbicular, 
slightly higher than long, compressed, early growth-stages flattened. Umbones just 
anterior to median, obtusely angular. Postero-dorsal outline strongly convex, steep, 
meeting almost semicircular ventral margin in an ill-defined angle ; anterior outline 
very feebly convex, steep. Escutcheon narrow, no lunule. Surface, up to mid- 
growth, bearing obtusely angular ridges, widely separated except near umbo, the 
last two 3 mm. apart ; later growth-stages bearing only rather fine concentric 
threads. 

Holotype. No. LL.35189. The only specimen. 

Locality and horizon. Nchia stream, 2 miles W.N. W. of Mandawa, Tangan- 
yika ; Callovian. 

Remarks. This species differs from A. huralensis Stefanini, recorded below (p. 89), 
in its taller form, in the wider spacing of its obtuse concentric ridges, and in the ab- 
sence of such ridges in later stages of growth. 

Astarte unilateralis J. de C. Sowerby 
PL 14, figs. 2, 3 

18406. Astarte unilateralis J. de C. Sowerby : 327, pi. 21, fig. 14. 

1863. Astarte hermanni Oppel : 272. 

1865. Astarte unilateralis Sow. ; Salter in Strachey : 97, pi. 23, fig. 10. 

1913. Astarte hermanni Oppel ; Holdhaus : 440, pi. 99, figs. 7-1 1, 14. 

Material. Two specimens (nos. LL.35118-19), ex B.P. Coll. 

Locality and horizon. Lonji creek, W. of Mandawa, Tanganyika ; Callovian? 



88 JURASSIC BIVALVIA AND GASTROPODA 

Remarks. Specimens of this species from the Spiti Shales were described very 
fully by Holdhaus, but it is not clear why he preferred Oppel's specific name to the 
earlier one of Sowerby. Sowerby's type and the specimen from the Spiti Shales 
figured by Salter are both in the British Museum (Natural History) , where there are 
also numerous topotypes from Cutch. The species is characterized by its strongly 
inequilateral cuneiform shape and its strongly convex postero-dorsal outline, which in 
many specimens rises appreciably above the umbo before beginning to slope steeply 
downwards to join the low posterior margin in an uninterrupted curve. The 
earlier growth stages are ornamented with well separated, regular, angular concentric 
folds, which later are replaced by irregular rugae. This is the first record of the spe- 
cies from East Africa. The specimens recorded are up to about 44 mm. long and 
quite typical as regards shape and ornament. 

In Cutch this species occurs most commonly in the Callovian athleta Beds and 
Oxfordian Dhosa Oolite. Ill-preserved specimens which appear to be referable to it 
occur in the Callovian Chari beds and also in the Upper Oxfordian. 

Astarte sowerbyana Holdhaus 
PI. 13, figs. 6a, b 

1840c. Astarte major J. de C. Sowerby, pi. 61, fig. 1 and explan. (non Astarte elegans major 

Zieten). 
1913. Astarte sowerbyana Holdhaus : 443, pi. 99, figs. 12, 13, 15 ; pi. 100, fig. 1. 
1933. Astarte krenkeli Dietrich : 40, pi. 4, figs. 62, 64, 66. 

Material. Three specimens (including nos. L. 52688, LL. 35120), partly ex B.P. 
Coll. 

Localities and horizons. Lihimaliao creek, Mandawa area, Tanganyika ; 
Upper Oxfordian. N. of Kipande, also 1 mile N.W. of Tendaguru hill, Tanganyika ; 
Upper Kimmeridgian, Nerinella Bed. 

Remarks. This species differs from A . unilateralis in its more ovate outline and 
larger size, although the difference in size is not so marked in the specimens from 
the Spiti Shales described by Holdhaus as in those from India and East Africa. In 
the African specimens, as in those from India, there is some variation in the relative 
elongation of the shell. Sowerby's type specimen of A . major, which is in the British 
Museum (Natural History), is a relatively elongate shell and very similar to Dietrich's 
type of A. krenkeli. It is strange that Dietrich made no reference to Sowerby's 
species. In early stages of growth A. sowerbyana, like A. unilateralis, bears con- 
centric folds. In later stages these are replaced by rather distant concentric undula- 
tions in some specimens and by irregular corrugations in others. 

In Cutch this species occurs at several localities in the Upper Oxfordian (Argovian) 
Astarte Bed, and it reappears in the Tithonian of Moondan and elsewhere. 

Astarte episcopalis de Loriol 

1897. Astarte duboisi d'Orbigny ; de Loriol : 88, pi. 12, fig. 13 (non d'Orbigny). 
1901. Astarte episcopalis de Loriol : 72, pi. 5, figs. 1, 2. 



FROM TANGANYIKA AND KENYA 89 

Material. Four specimens (nos. LL. 16837-40). 

Locality and horizon. Usigiwa river, 6 miles W.S.W. of Kiwangwa, Baga- 
moyo hinterland, Tanganyika ; Upper Oxfordian. 

Remarks. The length of the largest specimen referred to this species is 72 mm. 
The shell is ovate, with the height equal to about three-quarters of the length, and 
is strongly inequilateral and of moderate and even convexity. The umbo is slightly 
obtuse and not quite terminal. The postero-dorsal outline is of moderate convexity, 
rising at first to a level slightly above that of the umbo, and then sloping down to 
form a rounded-off, obtuse angle with the slightly oblique and flattened posterior 
margin ; the antero-dorsal outline is scarcely excavated. The ventral and antero- 
ventral margins are of strong convexity. The lunule is shallow and there is no 
escutcheon. The surface bears concentric undulations, which are regular in early 
stages of growth, but later become very irregular. 

The African specimens do not appear to differ in any features of importance from 
A. episcopalis which occurs typically in the " Middle Oxfordian " of the Bernese 
Jura. Of the other species now recorded from East Africa, A. muelleri Dacque is 
more trigonal in outline. A. subobovata Dietrich is more rounded posteriorly and 
less elongate, A . recki Dietrich has a more strongly convex postero-dorsal outline, 
and A. mitoleensis sp. nov. is more elongate and tapers more towards its posterior 
end. 

Astarte huralensis Stefanini 
PI. 15. ng. 1 

1939. Astarte huralensis Stefanini : 234, pi. 24, figs. 19, loa-c. 
i960. Astarte sp. nov. ; Joubert, pi. 9, figs. 4a, b. 

Material. Numerous specimens (nos. L. 92123, L. 92236-39), preserved on the 
surface of blocks of limestone. 

Locality and horizon. Dusse, i^ miles S.E. of Rahmu, N.E. Kenya ; Upper 
Oxfordian, Seir Limestones. 

Remarks. The specimens now recorded agree well in size and ornament with 
Stefanini's figures, which do not, unfortunately, show the outline of the shell very 
clearly. The Kenya specimens are up to about 9 mm. in length, rectangularly ovate 
to subtrigonal, with the length slightly exceeding the height, and not strongly in- 
flated. The umbo, which is obtusely angular and not incurved, is not quite terminal, 
the anterior margin of the shell projecting slightly beyond it. The dorsal margin is 
convex, meeting the nearly straight and vertical posterior margin in a rounded-off, 
obtuse angle. The ventral margin is strongly convex and the antero-dorsal outline 
is moderately excavated below the beak. The ornament consists of relatively wide- 
spaced, obtusely angular concentric ridges, the crests of which are about i-8 mm. 
apart ; no subordinate threads are present. 

The most closely comparable European species appears to be Astarte cingulata 
Contejean (i860 : 267, pi. 11, figs. 5-10), from the Kimmeridgian, in which the out- 
line of the shell is more trigonal. A. huralensis was described originally from the 
" Oolitico medio " (? Oxfordian) of southern Somalia. 



9 o JURASSIC BIVALVIA AND GASTROPODA 

Astarte mandawaensis sp. nov. 
PI. 14, figs. 6a, b 

Diagnosis. Of medium size (length of holotype 38 mm.), ovate, rather strongly 
inequilateral, length exceeding height, beak at anterior third of length ; shell well 
inflated for the genus. Umbo obtusely angular, depressed, slightly incurved to 
prosogyrous beak. Postero-dorsal outline rather strongly convex, level with umbo 
anteriorly, down-curved posteriorly, where it forms an obtuse angle with the some- 
what flattened posterior margin ; ventral and anterior margins forming an uninter- 
rupted curve of strong convexity ; antero-dorsal outline strongly concave. Lunule 
broad, flattened and deep, bordered by well-defined ridge ; escutcheon narrow. 
Ornament of irregular concentric undulations which are broad and relatively few on 
anterior two-thirds of surface but increase in number by intercalation or bifurcation 
on posterior part, where they are consequently of diminished width. 

Anterior cardinal tooth of left valve stout and prominent, sloping back from beak 
and separated by narrow space from lunular margin ; posterior cardinal tooth 
elongate, slightly curved, forming very acute angle with ligamental nymph. 

Holotype. No. LL.35121, ex B.P. Coll. The only specimen. 

Locality and horizon. Lonji creek, W. of Mandawa, Tanganyika ; Upper 
Kimmeridgian. 

Remarks. Although the postero-ventral part of the holotype is broken away, 
the well inflated, ovate form of the shell is very distinctive for an astartid, while the 
ornament is also characteristic. It differs from the approximately contemporaneous 
East African species A. weissermeli Dietrich, recorded below (p. 92), in its more 
elongate outline, its broader and more unevenly arranged concentric undulations, 
and its deep, distinctly bordered lunule. 

Astarte lonjiensis sp. nov. 
PI. 14, fig. 1 

Diagnosis. Large (length of holotype 74 mm.) , ovate with slight trigonal tendency, 
highly inequilateral, height six-sevenths of length ; inflation rather weak. Umbo 
almost terminal, slightly incurved, rather sharply rounded in outline ; postero- 
dorsal outline continuous with that of umbo, at first convex and rising very slightly 
above level of latter, but almost straight and sloping gently downwards along greater 
part of length ; it forms a slightly obtuse angle with the short, straight, subvertical 
posterior margin. Antero-dorsal outline steep, slightly concave ; ventral margin 
very strongly convex. Lunule narrow, moderately excavated ; no escutcheon. 
Early growth-stages ornamented with regular, rather closely spaced concentric ribs, 
which in later stages are replaced by coarse, irregular rugae. Interior not exposed. 

Holotype. No. LL.35122, ex B.P. Coll. The only specimen. 

Locality and horizon. Lonji creek, W. of Mandawa, Tanganyika ; Upper 
Kimmeridgian. 



FROM TANGANYIKA AND KENYA 91 

Remarks. This species is less tumid than A. sowerbyana, has a more strongly 
convex ventral margin, and is more closely ribbed on its umbonal region. It is less 
orbicular in shape than A. recki Dietrich, which is abundant in the Upper 
Jurassic at Tendaguru. 

Astarte subobovata Dietrich 
PI. 15, %. 4 

1933. Astarte subobovata Dietrich : 40, pi. 5, figs. 68, 74 ; pi. 9, fig. 141. 

Material. One specimen (no. L. 52683). 

Locality and horizon. Maimbwi river, Tendaguru, Tanganyika ; Upper 
Kimmeridgian, " Trigonia smeei " Bed. 

Remarks. Dietrich's two figured syntypes showing the exterior of the shell 
(pi. 5, fig. 68 ; pi. 9, fig. 141) differ considerably in shape. A study of the figures 
suggests, however, that the distinction between this species and the closely com- 
parable species A. recki lies mainly in the broadness of the concentric folds on the 
main part of the surface, which rather resemble those of a Cardinia. Other points 
of distinction are the less strongly convex postero-dorsal margin and the stronger 
inflation of the shell, especially in the umbonal region. On the basis of such differ- 
ences, a single specimen in the material studied is assigned to A. subobovata. 

It is not clear why Dietrich not only commented on the similarity between this 
species and the Lower Cretaceous species A. obovata J. de C. Sowerby but also as- 
signed a specific name to it suggesting affinity with the form in question. In A. 
obovata the concentric folds on the main part of the surface of the shell are of much 
smaller amplitude than in A. subobovata and not in the least reminiscent of those of 
a Cardinia. 

Astarte recki Dietrich 
PI. 14, figs. 4, 5 
1933. Astarte recki Dietrich : 40, pi. 4, fig. 60 ; pi. 5, figs. 69-71. 

Material. Several specimens. 

Localities and horizons. Several localities around Tendaguru, Tanganyika ; 
Upper Kimmeridgian, Nerinella and " Trigonia smeei " Beds. 

Remarks. A particular characteristic of this large species is the broad convexity 
(almost an obtuse angularity) of the anterior part of the postero-dorsal margin, which 
rises well above the level of the beak. The length of the shell exceeds the height very 
slightly and the anterior margin projects beyond the beak to a variable extent, but 
usually not very much. In most specimens the posterior margin is a little flattened, 
but in some it is convex and merges with the ventral margin in an even curve. Up 
to a height of 25 mm. the shell bears closely and regularly spaced concentric ridges, 
but in later growth-stages these are replaced by irregular rugae and corrugations. 
The length of the largest specimen examined is about 90 mm. 



92 JURASSIC BIVALVIA AND GASTROPODA 

Astarte weissermeli Dietrich 
PI. 13, figs. 2, 3 
1933. Astarte weissermeli Dietrich : 41, pi. 6, figs. 75-80. 

Material. Several specimens. 

Localities and horizons. Nitongola creek, Maimbwi river, Kindope valley, 
and £ mile S. of Nautope, all Tendaguru district, Tanganyika ; Upper Kimmeridgian, 
" Trigonia smeei " Bed. Mpilepile stream, 800 yards E.N.E. of junction of main 
road and Mahokondo road, Mitole, northern Mandawa area, Tanganyika ; Upper 
Kimmeridgian. 

Remarks. This is a fairly strongly and evenly inflated, suborbicular species with 
a rather prominent umbo situated at about the anterior third of the length of the 
shell and with ornament of strong, irregular concentric corrugations. The largest 
specimen in the material studied is about 30 mm. high. 

Astarte mitoleensis sp. nov. 
PL 13, fig. 1 

Diagnosis. Large (length of holotype 74 mm.), ovate, height four-fifths of length, 
strongly inequilateral ; inflation moderate. Umbo not quite terminal, incurved, 
convexly subangular in outline ; postero-dorsal outline strongly convex, rising at first 
well above umbo and then curving down to form a rounded-off, obtuse angle with 
the rather low, almost straight, vertical posterior margin. Antero-dorsal outline 
strongly excavated ; ventral and antero-ventral margins of moderately strong 
convexity. Lunule well excavated ; no escutcheon. Median part of flank flattened 
ventrally. Ornament consisting of very irregular concentric undulations and rugae, 
not more evenly arranged in early than in later growth-stages. 

Holotype. No. LL. 35123, ex B.P. Coll. The only specimen. 

Locality and horizon. Mpilepile stream, 1300 yards E.N.E. of Mitole road 
junction, northern Mandawa area, Tanganyika ; Upper Kimmeridgian. 

Remarks. This species differs from Astarte stuhlmanni (Miiller), Neocomian, 
Tanganyika, and from A. subobovata Dietrich, Upper Kimmeridgian, Tanganyika, 
in its less inflated form, its more strongly excavated antero-dorsal outline, and its flat 
posterior margin. Compared with A. episcopalis de Loriol, it is higher at its poste- 
rior end and less elongate. It very closely resembles the European Aptian species 
Astarte obovata J. Sowerby. 

Subgenus LECKHAMPTONIA Cox & Arkell 1948 

Astarte (Leckhamptonia) hobleyi sp. nov. 
PI. 15, figs. 2«, b 

Specific name. After the late C. W. Hobley, a pioneer in the investigation of 
the geology of Kenya. 



FROM TANGANYIKA AND KENYA 93 

Diagnosis. Of medium size (length of larger specimen c. 30 mm.), rectangular, 
height two-thirds of length, beaks at about anterior third of length ; inflation slight. 
Umbo very broad, not incurved ; postero-dorsal outline straight, horizontal, form- 
ing a slightly obtuse angle with the straight or feebly convex posterior margin ; ven- 
tral margin straight, parallel with postero-dorsal outline ; antero-dorsal outline very 
slightly concave, gently inclined ; anterior margin of feeble convexity. Ornament 
consisting of almost equidistant, well separated, erect lamellae, with fine growth- 
threads in their intervals. 

Holotype and paratype. Holotype, no. LL.35045. One paratype only, no. 
LL.35046. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This species seems closely related to Astarte (Leckhamptonia) inter- 
lineata Morris & Lycett, of the Bajocian and Bathonian of England, but it is much 
larger. It bears some resemblance to the internal mould from the Upper Lias of 
Germany figured by Roemer (1836 : 120, pi. 8, fig. 3) as "Corbis laevis Sow.? " and 
re-named Astarte sublaevis by d'Orbigny. 



Genus COE LAST ARTE Boehm 1893 
Coelastarte dietrichi sp. nov. 

J 933- Astarte (Coelastarte) cf. cotteausia (d'Orb.) de Loriol ; Dietrich : 42, pi. 4, fig. 61 (non 
A. cotteausia d'Orbigny). 

Diagnosis. Shell of medium size (length of holotype c. 40 mm.), rectangularly 
ovate, well elongated (length to height ratio 5:3), compressed. Beaks at about 
anterior fifth of length, pointed, directed downward to some extent, with convex 
dorsal margin rising above them ; antero-dorsal outline concave. Posterior margin 
rounded except in earlier stages of growth, ventral margin flattened. Concentric 
undulations strong and regular in earlier stages of growth, bending upward in a well- 
defined angle posteriorly, irregularly spaced and rather weaker in later growth-stages. 

Holotype and paratype. The specimen figured by Dietrich, which it has not 
been possible to examine, is designated as holotype. One specimen (no. L. 521 13) in 
the material examined is the only paratype. 

Locality and horizon. Nitongola creek, Tendaguru, Tanganyika ; Upper 
Kimmeridgian, " Trigonia smeei " Bed. The holotype came from the same horizon 
in the bed of the Maimbwi river, Tendaguru. 

Remarks. This species was considered by Dietrich to be closely comparable to 
Astarte cotteausia d'Orbigny as figured by de Loriol (1875 : 100, pi. 15, fig. 42) from 
the Lower Kimmeridgian of France, but it is more elongated and has a more pro- 
nounced convexity of the antero-dorsal outline. According to Cottreau (1929 : 101), 
d'Orbigny's holotype of A. cotteausia is too ill-preserved to be worth figuring. 
Astarte rzehaki Boehm (1883 : 558, pi. 62, fig. 33), Tithonian of Moravia, is higher at 



94 JURASSIC BIVALVIA AND GASTROPODA 

its posterior extremity. Although species of Coelastarte are well known to be vari- 
able, it seems desirable to regard the East African form as a separate species. 

Genus PRAECONIA Stoliczka 1871 
Praeconia rhomboidalis (Phillips) 

1829. Isocardia rhomboidalis Phillips : 128, pi. 3, fig. 28. 

1934a. Praeconia rhomboidalis (Phillips) ; Arkell : 251, pi. 33, figs. 14, 15. 

1948. Praeconia rhomboidalis (Phillips) ; Cox & Arkell : 28. 

Material. One specimen (no. LL. 35124), ex B.P. Coll. 

Locality and horizon. Hill-top N. of Lugoba on road to Msata, Tanganyika ; 
Callovian(P). 

Remarks. This specimen consists only of the posterior half of one valve, but is 
an unmistakable representative of the species, the geological range of which in Europe 
is from Bajocian to Oxfordian. 

Genus SEEBACHIA Holub & Neumayr 1882 
Seebachia janenschi Dietrich 
1933. Seebachia janenschi Dietrich : 43, pi. 4, figs. 57, 63, 64 ; pi. 5, figs. 67, 73. 

Material. Two specimens (including no. LL.35125), ex B.P. Coll. 

Locality and horizon. Mpilepile stream, 800 yards E.N.E. of junction of main 
road and Mahokondo road, Mitole, northern Mandawa area, Tanganyika ; Upper 
Kimmeridgian. 

Remarks. These specimens, which are preserved in a coarse conglomerate, are 
eroded, but have the unmistakable outline of B. janenschi. The larger is 52 mm. 
long. The type locality of the species is Tendaguru, where it occurs in the " Trigonia 
smeei " Bed. 

Superfamily LUGINACEA 

Family LUCINIDAE Fleming 1828 

Genus LUC IN A Bruguiere 1787 

Lucina sp. 

PI. 15, figs. 5a, b 

Material. Four internal moulds (nos. LL.35047-50). 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Description. Of medium size (length of largest specimen c. 22 mm.), suborbi- 
cular with a hexagonal tendency, length and height almost equal, umbones angular, 



FROM TANGANYIKA AND KENYA 95 

prosogyrous, at about anterior third of length ; inflation weak ; postero-dorsal 
region compressed, limited in each valve by a strongly curved ridge running from 
the umbo to the postero-ventral corner. 

Remarks. This lucinid is not referable to any species recorded from the Upper 
Lias of Europe, but the available specimens are too imperfect to serve as type 
material of a new species. The species is smaller and less rectangular than Lucina 
plana Zieten, in which, moreover, there is no compressed postero-dorsal area. The 
presence of this area also distinguishes it from the Bajocian species L. despecta 
Phillips, recorded below. 

Lucina despecta Phillips 
PI. 15, fig. 9 

1829. Lucina despecta Phillips : 150, pi. 9, fig. 8. 

Material. Numerous specimens, all in the form of moulds, on the surface of 
which traces of the original surface ornament are impressed. 

Localities and horizon. Kidugallo Station and i\ miles E. of Kidugallo 
Station, Central Railway, Tanganyika ; Bajocian, Station Beds. 

Remarks. The specimens are slightly longer than high, with the umbo broadly 
rounded, moderately prominent, and placed at about the posterior two-fifths of the 
length ; the length of a typical specimen is 18-5 mm. The gently sloping postero- 
dorsal outline forms a well-defined, obtuse angle with the nearly straight and verti- 
cal posterior margin. The anterior margin is feebly convex and prosocline in its 
general direction, joining the antero-dorsal margin in a broad curve. The surface is 
ornamented with concentric ridges which are about 1 mm. apart on the middle of the 
shell in the best-preserved specimen, with concentric threads in their intervals. Im- 
pressions of anterior and posterior lateral teeth are preserved. 

Lucina despecta, the holotype of which came from the Inferior Oolite of Yorkshire, 
has been misinterpreted by many authors and the name has been applied to speci- 
mens from later geological formations differing considerably from those from the 
type-horizon. No satisfactory figure of the species, in fact, exists in the literature, 
the original one of Phillips being a little foreshortened. The East African specimens 
now recorded have been compared with specimens of L. despecta from Yorkshire, 
and I can see no reason for separating them specifically from the English species. 
Lucina paradoxa Waagen (1867 : 621, pi. 31, figs. $a, b), from the Inferior Oolite of 
Germany, seems very close to L. despecta, although a little more elongate. 

Lucina cf. lirata Phillips 

References to descriptions of the typical L. lirata are as follows : 
1829. Lucina lirata Phillips : 140, pi. 6, fig. n. 
1934a. Lucina lirata Phillips ; Arkell : 278, pi. 41, figs. 1-3, 7. 

The form now recorded has been illustrated as follows : 
i960. Lucina sp. : Joubert, pi. 9, figs. 6a, b. 



q6 JURASSIC BIVALVIA AND GASTROPODA 

Material. One specimen (no. L. 92095). 

Locality and horizon. Kulong, 2 miles S.W. ot Muddo Erri, N.E. Kenya ; 
Callovian [?-Lo\ver Oxfordian], Muddo Erri Limestones. 

Remarks. The fossil now recorded is an ill-preserved specimen of a well-inflated, 
moderately large, suborbicular Lucina, the length and height of which were origin- 
ally just over 40 mm. It is of much the same size and shape as typical specimens 
of L. lirata from the Lower Oxfordian of England, but its well-marked and fairly 
evenly spaced concentric ridges are only about 0-75 mm. apart, whereas in specimens 
of L. lirata from the type-locality the corresponding distance is 1-1-5 mm. 

Lucina cutleri sp. nov. 
PL 15, figs. 3«, b 

Specific name. After the late W. E. Cutler, the first leader of the British Museum 
East Africa Expedition. 

Diagnosis. Shell small (length 12 mm.), oval, only slightly longer than high, 
feebly inflated. Umbo very broadly rounded, placed at anterior two-fifths of 
length, level with feebly convex postero-dorsal margin, which makes a fairly well- 
defined, obtuse angle with the posterior margin. Posterior margin a little flattened, 
but merging in an even curve with the strongly convex ventral margin, which is also 
continuous with the anterior margin. Antero-dorsal margin straight, visible in side- 
view of shell, sloping gently, and merging in a broad curve with the anterior margin. 
No lunule or escutcheon. Ornament consisting of narrow concentric ridges about 
one-third mm. apart in later growth-stages and separated by flat, smooth 
intervals ; ridges absent from antero-dorsal region, where margin is bordered by 
narrow, smooth area. 

Holotype. No. L.52141. The only specimen. 

Locality and horizon. Lilomba creek, Tendaguru, Tanganyika ; Upper 
Kimmeridgian, " Trigonia stneei " Bed. 

Remarks. In shape this species is rather like Lucina cardinalis Contejean (i860 : 
327, pi. 21, figs. 14, 15), from the Kimmeridgian of France, but it is very much 
smaller. In L. tarichensis de Loriol (1895 : 33, pi. 5, figs. 5, 6), from the Oxfordian 
of Switzerland, another much larger species, the antero-dorsal outline of the shell 
is more excavated. 

Family UNICARDIIDAE Fischer, 1887 

Genus MACTROMYA Agassiz 1843 

Mactromya eamesi sp. nov. 
PL 15, figs. 8a, b, c 

Specific name. After Dr. F. E. Eames, Chief Palaeontologist of the British 
Petroleum Co., Ltd. 



FROM TANGANYIKA AND KENYA 97 

Diagnosis. Small for genus (length 17 mm.), elongate-ovate, slightly inequi- 
lateral, height less than two-thirds of length, beaks at anterior two-fifths of length ; 
inflation moderate for genus. Umbones very broadly rounded, well incurved to 
slightly prosogyrous beaks, and projecting a little above antero-dorsal outline, which 
slopes gently and meets the feebly convex posterior margin in a broad curve ; 
ventral margin of very feebly convexity, symmetrical ; anterior margin of feeble 
convexity, not much shorter than posterior margin ; antero-dorsal outline feebly 
concave, scarcely sloping. Ornament consisting of irregular concentric ribs and 
rugae. 

Holotype. No. LL. 35127, ex B.P. Coll. No other material has been examined. 

Locality and horizon. Near site of Mandawa well no. 1, Tanganyika ; Bajo- 
cian(?). 

Remarks. This shell is even more elongate than Mactromya aequalis Agassiz 
(1843 : 196, pi. gd, figs. 5-8), a species of Bathonian-Callovian age, and is also more 
strongly inflated. 

Mactromya aequalis Agassiz 
PI- 15, fig. 7 

1843. Mactromya aequalis Agassiz : 196, pi. gd, figs. 5-8. 

1912. Mactromya aequalis Agassiz ; Lissajous : 97, pi. 12, fig. 11. 

1915^. Arcomya bicorrugata Cossmann : 12, pi. 1, fig. 5 ; pi. 2, figs. 9-1 1 ; pi. 3, figs. 14-16. 

1929. Mactromya rugosa auct. ; Weir, 34, pi. 3, figs. 16, 17 {non 18) (non Roemer). 

1935a. Mactromya aequalis Agassiz ; Cox : 183, pi. 19, figs. 16, 17a, b. 

1939. Mactromya aequalis Agassiz ; Stefanini : 259, pi. 27, fig. 1. 

i960. Mactromya aequalis Agassiz ; Joubert, pi. 10, figs, ja, b. 

Material. Several specimens. 

Localities and horizons. 3! miles W. of Melka Biini, N.E. Kenya ; Callovian, 
Rukesa Shales. 14 miles W.S.W. of Rahmu, also Muddo Erri and Kulong, 2 miles 
S.W. of Muddo Erri, all N.E. Kenya ; Callovian [?-Lower Oxfordian], Muddo Erri 
Limestones. 

Remarks. These poorly preserved specimens are similar to those from British 
Somaliland which I figured in 1935. They are characterized by the irregularity of 
their concentric ridges and corrugations. 

Mactromya quadrata (Roemer) 
PI. 15, figs. 11a, b 

1836. Mya rugosa Roemer : 125, pi. 9, figs. 16, 17 (non Gmelin). 

1836. Mya quadrata Roemer : 126. 

1840. Lutraria concentrica Munster in Goldfuss : 258, pi. 153, figs. 5a, b. 

1843. Mactromya rugosa (Roemer) ; Agassiz : 197, pi. gc, figs. 1-23. 

1872. Lucina rugosa (Roemer) ; de Loriol : 266, pi. 16, fig. 1. 

1912. Mactromya rugosa (Roemer) ; Lissajous : 97, pi. 12, fig. 12. 

Material. Four specimens. 

Localities and horizons. Kailta, Golberobe hills, N.E. Kenya ; Oxfordian, 



98 JURASSIC BIVALVIA AND GASTROPODA 

Golberobe Beds. 17 miles S. of Rahmu, N.E. Kenya ; Upper Oxfordian, Seir 
Limestones. 3 miles N.E. of Melka Dakacha, N.E. Kenya ; Upper Kimmeridgian, 
Dakacha Limestones. Just W. of Mabokweni, 4 miles N.W. of Tanga, Tanganyika ; 
Kimmeridgian. 

Remarks. This species, like M. aequalis, from which it scarcely differs, is 
characterized by its rather elongate outline and by the irregularity of its concentric 
ridges, which very commonly are undulating in places. 



Family FIMBRIIDAE Nicol 1950 

Genus FIMBRIA Mergele von Muhlfeld 181 1 

Fimbria kidugalloensis sp. nov. 
PI. 16, figs. la, b 

Diagnosis. Shell of small-medium size (length 32 mm.), elongate, rather weakly 
inflated. Umbones subangular, slightly anterior to median, protruding above 
postero-dorsal outline, which is straight, sloping gently to low posterior extremity 
of shell. Ventral margin of very feeble convexity ; antero-dorsal outline well 
excavated ; anterior margin evenly rounded. Ornament consisting of closely and 
rather unevenly spaced, thin concentric ridges, typically about 0-4 mm. apart in 
later growth-stages ; many intervals between them bear one or more weak concentric 
threads, together with traces of radial threads. 

Holotype. No. L. 54103. The only specimen. 

Locality and horizon. i£ miles E. of Kidugallo Station, Central Railway, 
Tanganyika ; Bajocian, Station Beds. 

Remarks. The genus Fimbria is rare in the Bajocian. The species now described 
is characterized by the fineness and close spacing of its concentric ridges. F. aspera 
(Lycett) (1850 : 423, pi. 11, fig. 7), from the English Inferior Oolite, is much more 
coarsely ornamented. The Kimmeridgian species F. formosa (Contejean) 
(i860 : 275, pi. 13, figs. 1-3) has equally fine concentric ornament but is less elongate. 

Fimbria sp. " A " 
PI. 15, fig. 6 

Material. Several specimens. 

Localities and horizons. Hills S. of Rahmu-Melka Murri road at localities 11 
miles and 13 miles W. of Rahmu, N.E. Kenya ; Callovian, Rukesa Shales. Hills S. 
of Rahmu-Melka Murri road at locality 9 miles W. of Rahmu ; also Muddo Erri, 
N.E. Kenya ; Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Remarks. Two species of Fimbria which occur in the Rukesa Shales and Muddo 
Erri Limestones are represented in the material studied only by specimens which are 
incomplete, much eroded, or in the form of internal moulds. The largest specimen 



FROM TANGANYIKA AND KENYA 09 

of the first of these species, which may be recorded as " species A ", is about 60 mm. 
long. The ornament consists of closely and irregularly arranged concentric ridges, 
the average distance between which varies to some extent in different specimens but 
is always well below 1 mm. No trace of radial ornament can be detected. This 
form is less inflated than F. lajoyei (d'Archiac) (1843 : 372, pi. 27, figs, la-d), from 
the Bathonian of north-western Europe, and differs further in the closer arrange- 
ment of its concentric ridges and in the absence of radial ornament. In an English 
Great Oolite specimen of F. lajoyei figured by Morris & Lycett (1853, pi. 7, fig. 12) 
the ribs are more closely spaced in later stages of growth than in early stages, but 
they are further apart than in the East African specimens. 

Fimbria sp. " B " 

PI. 15, fig. 12 

i960. Corbis lajoyei d'Archiac ; Joubert, pi. 9, fig. ja. 

Material. About four specimens. 

Localities and horizon. Muddo Erri, and Kulong, 2 miles S.W. of Muddo Erri, 
N.E. Kenya ; Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Remarks. A second species of Fimbria found in the Muddo Erri Limestones is 
the one of which a broken specimen has been figured by Joubert (i960) as Corbis 
lajoyei. It has relatively distant concentric ridges with intervals in which radial 
threads are well seen. This species is probably distinct from the true F. lajoyei, 
but this point cannot be decided definitely owing to the poor state of preservation of 
the material. Several of the Kenya specimens, like the one represented in Joubert's 
pi. 9, fig. 76, are internal moulds and quite unidentifiable. 

Fimbria quennelli sp. nov. 
PL 16, fig. 7 

Specific name. After Mr. A. M. Quennell, formerly Director of the Tanganyika 
Geological Survey. 

Diagnosis. Large, with the height four-fifths of length (93 mm. in holotype), 
broadly rounded anteriorly, tapering posteriorly to a low, subtruncate extremity. 
Limbo moderately prominent, submedian ; postero-dorsal outline almost straight, 
sloping to meet low subvertical posterior margin in a rounded-off , obtuse angle ; 
antero-dorsal outline well excavated ; ventral margin asymmetrical, strongly con- 
vex anteriorly, more weakly convex posteriorly. An obtuse ridge, best seen in later 
stages of growth, runs from postero-ventral angle of shell towards umbo. Ornament 
consisting of coarse, rounded concentric ribs separated by much narrower furrows 
and crossed by weak radial riblets, best seen on anterior half of surface. Ventral 
margin crenulated internally. 

Holotype and paratype. Holotype, no. LL.16841 and one imperfect paratype. 



ioo JURASSIC BIVALVIA AND GASTROPODA 

Locality and horizon. Usigiwa river, 6 miles W.S.W. of Kiwangwa, Bagamoyo 
hinterland, Tanganyika ; Upper Oxfordian. 

Remarks. In few of the described Jurassic species of Fimbria do specimens 
approach the present ones in size. De Loriol (1872 : 260 ; 1888 : 240, pi. 26, figs. 
1, 2), however, has recorded some equally large specimens, from the Lower Kim- 
meridgian of France and Switzerland, under the name Corbis buvignieri ; they differ 
from the form now recorded in the absence both of the diagonal ridge and of radial 
ornament. In Corbis jaccardi Rollier (1913 : 249, pi. 17, fig. 1), an equally large 
form from the Upper Oxfordian of Switzerland, a diagonal ridge is present but the 
shell is more elongate than in the African specimens, the concentric ribs are narrower, 
and radial ornament is lacking. Corbis episcopalis de Loriol (1891 : 193, pi. 21, 
figs. 2-4) bears radial ornament, but is much smaller than the specimens now 
described and tapers less towards its posterior extremity. 



Fimbria sp. " C " 

PL 15, fig. 10 

Material. One specimen (no. LL. 35126), ex B.P. Coll. 

Locality and horizon. Lonji creek, W. of Mandawa, Tanganyika. Upper 
Kimmeridgian. 

Remarks. This specimen is a broken and eroded left valve, about 53 mm. long, 
with a broadly rounded umbo which is slightly posterior to median in position. 
The ornament consists of broad, rounded, depressed ribs which are unequal in width 
and separated by narrower intervals in which there are traces of radial threads. 
The broadness of the ribs is a particularly noticeable feature. The form from the 
Lower Kimmeridgian of Valfin, in the French Jura, described by de Loriol (1888 : 
240, pi. 26, figs. 1, 2) as Corbis buvignieri Deshayes, and re-named Corbis canaliculata 
by Rollier (1913 : 256), is comparable in this respect, but it is a larger shell and its 
ribs are not quite so broad. It is most probable that the specimen now recorded 
belongs to a new species. 



Genus SPHAERA J. Sowerby 1822 
Sphaera subcorrugata Dietrich 
1933. Corbis {Sphaera) subcorrugata Dietrich : 49, pi. 6, figs. 81, 82. 

Material. Two specimens (nos. L.51169, L.51891). 

Localities and horizons. N. of Kipande, near Tendaguru, Tanganyika ; 
Upper Kimmeridgian, Nerinella Bed. 3 miles N.N.W. of Tapaira, near Tendaguru ; 
Upper Kimmeridgian, " Trigonia smeei " Bed. 



FROM TANGANYIKA AND KENYA 101 

Genus SPHAERIOLA Stoliczka 1871 

Sphaeriola madridi (d'Archiac) 
PL 16, figs. 3, 4 

1843. Cardium madridi d'Archiac : 373, pi. 25, figs, ja, b. 

1867. Corbis (Sphaera) madridi (d'Archiac) ; Laube : 38, pi. 3, fig. 4. 

1921. Unicardium (Sphaeriola) madridi (d'Archiac) ; Cossmann, pi. 3, figs. 14, 15. 

1948. Sphaeriola madridi (d'Archiac) ; Cox & Arkell : 35. 

Material. Several specimens. 

Locality and horizon, i mile N. of Asaharbito, N.E. Kenya ; Bathonian [? or 
Callovian], Asaharbito Beds. 

Remarks. These specimens do not appear to be distinguishable from S. madridi. 
The concentric corrugations which form their ornament are somewhat unequal and 
irregularly distributed, much as in the specimens figured by Laube. It is probable 
that the regularity of their arrangement in d'Archiac's original figure is due to their 
inaccurate representation by the artist. It has not been possible to expose the 
hinge-teeth in any of the African specimens and to confirm that the dentition is that 
of a Sphaeriola rather than of the externally similar genera Mactromya and Uni- 
cardium. A fragment of an internal mould in the material studied shows, however, 
traces of crenulations of the ventral margin, such as are found in Sphaeriola and not 
in the other two genera. The identification of Sphaeriola is important stratigraphi- 
cally, as the known range of the genus is from Lias to Callovian and it is particularly 
abundant in the Bathonian. 



Superfamily CARDIACEA 

Family CARDIIDAE Goldfuss 1820 

Genus PROTOCARDIA Beyrich 1845 

Protocardia africana sp. nov. 
PL 16, figs. 2a, b, c 

19086. Protocardia cf. striatula Sow. ; Thevenin : 27, pi. 4, fig. 5. 

Diagnosis. Of small-medium size (length of largest specimen 21 mm.), suborbi- 
cular, equilateral, height slightly less than length, shell evenly and strongly inflated. 
Umbones rather narrowly rounded, prominent, well incurved to the very slightly 
prosogyrous beaks. Margins forming a strongly convex and uninterrupted curve ; 
anterior end of shell only slightly less broad than posterior end. No diagonal ridge. 
Flank unornamented except for growth-lines ; posterior area not flattened, with 
about 30 granose radial riblets. 

Holotype and paratypes. Holotype, no. LL.35603. Several paratypes (nos. 
LL.35063-72). 



102 JURASSIC BIVALVIA AND GASTROPODA 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This species resembles the European Upper Lias-Bajocian species 
Protocardia subtrttncata (d'Orbigny) (= Cardium truncatum Goldfuss, 1837 ■ 218, 
pi. 143, figs, ioa-c, non Phillips) in size and in the general shape of the shell ; it 
differs, however, in its slightly more prominent umbones, in the absence of a diagonal 
ridge, in its more rounded posterior margin, and in the presence of granules on the 
radial riblets on its posterior area. Protocardia ferruginea Rollier ( = P. striatula 
Benecke 1905 : 228, pi. 17, figs. 1-4, non J. de C. Sowerby), to which the Yorkshire 
Dogger species erroneously attributed to P. striatula (J. de C. Sowerby) by Phillips 
(1829, pi. 11, fig. 7) also probably belongs, commonly attains a considerably larger 
size than that of the present East African specimens, and the riblets on its posterior 
area are not so conspicuously granose. 



Protocardia besairiei sp. no v. 

PL 16, figs. 8, ga, b, 10 

Specific name. After Monsieur H. Besairie, who collected specimens of the 
species from Madagascar. 

Diagnosis. Of medium size (length c. 30 mm.), ovate, strongly inequilateral, 
height about two-thirds of length, beaks from anterior fifth to quarter of length; 
inflation moderately strong. Umbones broadly rounded, depressed, well incurved 
to the prosogyrous beaks. Postero-dorsal margin subhorizontal or gently sloping, 
forming a rounded-off, obtuse angle with more or less oblique, flattened posterior 
margin ; ventral margin of feeble convexity ; anterior margin strongly convex, 
anterior end of shell relatively narrow for a Protocardia ; antero-dorsal outline 
strongly concave. A weak diagonal ridge is present, bordering a rather flattened 
posterior area. Flank ornamented with somewhat irregular and unequal, rounded 
concentric ribs. Posterior area with fine radial grooves separating weak riblets. 

Holotype and paratypes. Holotype, no. LL.35128, ex B.P. Coll., the only 
specimen from East Africa examined. Paratypes, nos. L. 74972-79, from Mada- 
gascar. 

Localities and horizon. Lihimaliao creek, at a point near Mbaru creek, 
Mandawa area, Tanganyika (type-locality) ; Bajocian (?), Pindiro Shales. Mont 
Bovy, Maevatanana, N.W. Madagascar ; Bajocian. 

Remarks. No closely comparable described species can be cited. Obvious 
differences which distinguish it from P. beneckei Rollier (1912 : 113, 121) (= Proto- 
cardia sp. ; Benecke, 1905 : 231, pi. 17, figs. 7, 8), from the Lower Bajocian of 
Lorraine, are its ovate and inequilateral, rather than orbicular, outline, and its 
rugose, irregularly ornamented flank. 



FROM TANGANYIKA AND KENYA 103 

Protocardia bipi sp. nov. 
PL 17, figs, i, 2, 3«, b 

Specific name. After " B.P. " (British Petroleum Co. Ltd.), whose geologists 
collected the type material. 

Diagnosis. Of medium size (length of largest specimen c. 28 mm.), very variable 
in shape and proportions, ovate to trigonally ovate, subequilateral to strongly in- 
equilateral, beaks from anterior fifth of length to submedian, length exceeding height 
to a variable extent, inflation moderately strong. Umbones rather narrowly 
rounded, moderately prominent, well incurved to the beaks, which vary from ortho- 
gyrous to strongly prosogyrous according to their position. Postero-dorsal margin 
subhorizontal to gently sloping, posterior margin subvertical to strongly oblique, the 
two meeting in an even curve ; ventral margin symmetrical and feebly convex to 
strongly asymmetrical with posterior flattening ; anterior margin flat to feebly con- 
vex, its inclination variable. A distinct diagonal ridge, well marked in earlier 
growth-stages, delimits the slightly flattened posterior area. Flank unornamented 
except for growth-rugae. Posterior area with fine radial grooves. 

Holotype and paratypes. Holotype, no. LL.35129 ; several paratypes, in- 
cluding nos. LL. 35130-31 ; all ex B.P. Coll. 

Locality and horizon. Lihimaliao creek, at a point near Mbaru creek, Man- 
dawa area, Tanganyika ; Bajocian (?), Pindiro Shales. 

Remarks. This species is highly variable. The more elongate specimens show 
some approach in shape to P. besairiei, described above, but their beaks are not 
prosogyrous, the umbonal ridge does not persist to the postero-ventral angle of the 
shell, and the flank is more delicately ornamented. 

Protocardia consobrina (Terquem & Jourdy) 
PL 16, fig. 5 

1869. Cavdium consobrinum Terquem & Jourdy : 102, pi. 11, figs. 1-3. 

Material. Two specimens (nos. LL. 35 132-33), ex B.P. Coll. 

Locality and horizon. Changogo-Magindu track 4 miles from Changogo town, 
Tanganyika ; Callovian. 

Remarks. In these specimens, the larger of which is 27 mm. long, the shell is 
suborbicular and strongly and evenly inflated, with no diagonal ridge present at any 
stage of growth. The umbo is submedian and moderately prominent. The flank is 
smooth, while the posterior area bears shallow radial grooves, about 12 of which are 
distinguishable on the better preserved specimen, separating flattened radial riblets. 

I cannot distinguish between the African specimens and P. consobrina, as described 
and figured by its authors from the Bathonian of France. A French Callovian spe- 
cies, P. boonei Cossmann (1924 : 47, pi. 6, figs. 57, 58), is very similar in size and 
shape, but has finer and more numerous radial riblets on its posterior area. P. 



io 4 JURASSIC BIVALVIA AND GASTROPODA 

consobrina has been recorded from Madagascar by Douville and others, while Dacque 
(1910 : 30) has recorded a " Cardium sp. ", said to resemble this species, from Callo- 
vian beds at Km. 127 along the railway from Dar-es-Salaam to Morogoro. 

Protocardia rahmuensis sp. nov. 
PI. 17, figs. 4«, b 

Diagnosis. Of medium size (length of holotype c. 20 mm.), suborbicular, length 
and height almost equal, rather strongly inflated. Umbo prominent, median, with 
strongly convex outline. Antero-dorsal outline well excavated, anterior and vent- 
ral margins forming an even curve of strong convexity ; posterior margin slightly 
less convex than anterior one and forming a rather ill-defined, obtuse angle with 
ventral margin ; level of postero-dorsal margin slightly higher than that of antero- 
dorsal margin. Posterior area separated from flank by obtuse ridge and bearing 
nearly 20 radial riblets. Traces of fine concentric ridges preserved on flank of shell. 

Holotype. No. L. 92257, an internal mould. One or two further specimens are 
ill-preserved and should scarcely rank as paratypes. 

Localities and horizon. River section W. of Rahmu-El Wak road, 5^ miles 
S.W. of Rahmu (type-locality) ; Uacha, 6 miles S. of Rahmu, S.E. Kenya : both 
Oxfordian, Rahmu Shales. 

Remarks. The most closely comparable European Oxfordian species is Proto- 
cardia intexta (Minister), illustrated in a number of standard monographs by figures 
many of which have been subsequently re-named. In P. roemeri Rollier (for Cardium 
intextum Roemer (1839, P L J 9> n S- 3 > a l so de Loriol 1897, pi. 12, fig. 10)) the antero- 
dorsal and postero-dorsal outlines of the shell are less strongly excavated. Proto- 
cardia valbertensis de Loriol (1901 : 61, pi. 4, figs. 12-14), which Roeder (1882 : 89, 
pi. 3, figs. 4<z-c) had figured as P. intexta, closely resembles the African species in 
outline and ornament, but is much smaller. A poorly preserved Protocardia of 
about the same size which occurs commonly in the Golberobe Beds (Oxfordian) has 
a less prominent umbo and appears to belong to a different species. 

Protocardia schencki Muller 
PI. 17, figs. 5«, b 

1900. Protocardia schencki Muller : 544, pi. 19, figs. 12, 13. 
19146. Protocardia schencki Muller ; Hennig : 170. 
!933- Protocardia schencki Muller ; Dietrich : 52. 

Material. Numerous specimens. 

Localities and horizons. Scarp and stream bed at Kindope, N.N.W. of 
Tendaguru, Tanganyika ; Upper Kimmeridgian, Nerinella Bed. Tingutitinguti 
creek, Nitongola creek, and Kindope river, all near Tendaguru, Tanganyika ; Upper 
Kimmeridgian, " Trigonia smeei " Bed. Kinjele, 5 miles W. of Mtapaia, N. of 
Tendaguru, Tanganyika ; Upper Kimmeridgian, Indogrammatodon Bed. 



FROM TANGANYIKA AND KENYA 105 

Remarks. This is a small, orbicular, equilateral Protocardia, most specimens of 
which are evenly inflated, although a few have an obscure diagonal angulation. The 
largest specimens are about 15 mm. long. In one specimen which retains some of its 
original shell it can be seen that there are 15 or more riblets on the posterior area and 
that in earlier stages of growth these form a delicate reticulate pattern with closely 
arranged growth-threads. 

Protocardia suprajurensis (Contejean) 
PI. 17, fig. 6 

i860. Cardium suprajurense Contejean : 276, pi. 14, figs. 11, 12. 

1875. Cardium suprajurense Contejean ; de Loriol : 61, pi. 13, fig. 43. 

1878. Cardium suprajurense Contejean ; Struckmann : 94, pi. 4, figs. 5, 6. 

1905. Protocardia suprajurensis (Contejean) ; Schmidt : 173. 

Material. One specimen (no. LL.35I34), ex B.P. Coll. 

Locality and horizon. N. of Matapwa, Pindiro area, Tanganyika ; Upper 
Kimmeridgian. 

Remarks. The specimen consists of one valve of a subequilateral, moderately 
and evenly inflated representative of the Cardiidae, the height of which (c. 29 mm.) 
is approximately equal to the length. It is devoid of ornament except in later stages 
of growth, in which there are low, round-topped concentric ribs slightly more than 1 
mm. wide, separated by narrow intervals. No trace of radial ribbing can be seen on 
the posterior part of the surface, which, however, is rather obscured by matrix. 

This specimen seems to belong to Protocardia suprajurensis, a Kimmeridgian form 
originally described from the French Jura, where specimens attain about the same 
size. The affinities of the species have been disputed, Brauns having considered it 
to belong to Anisocardia. De Loriol and Struckmann, however, have expressed the 
opinion that it is a true cardiid, and it seems to be related to a group of species found 
in the Lower Cretaceous and similarly ornamented with concentric ribs. This group 
includes Cardium rothpletzi Dietrich, from the Neocomian of Tendaguru and C. 
sphaeroideum Forbes, from the Aptian of England, both of which attain a consider- 
ably larger size. Dietrich referred C. rothpletzi to his subgenus Tendagurium, but 
it does not appear to be closely related to the type-species of that taxon, and it is 
here included in Protocardia, sensu lato. 

Subgenus TENDAGURIUM Dietrich 1933 

Protocardia (Tendagurium) bannesiana (Contejean) 

i860. Cardium bannesianum {ex Thurmann, MS.), Contejean : 276, pi. 15, figs. i-$. 

1862. Cardium banneianum Thurmann ; Thurmann & Etallon : 181, pi. 22, figs. \a, b. 

1872. Cardium banneianum Thurmann ; de Loriol : 249, pi. 15, figs. 1, 2. 

1897. Cardium banneianum Thurmann ; Futterer : 600. 

1912. Nemocardium banneianum Thurmann ; Lissajous : 91, pi. 11, fig. 10. 

1930. Cardium banneanum Etallon ; Basse : 140, pi. 5, fig. 8. 

i960. Cardium (Protocardia?) bannesium Contejean ; Joubert, pi. io, fig. 6b. 



io6 JURASSIC BIVALVIA AND GASTROPODA 

Material. One specimen (no. L. 92194). 

Locality and horizon. Hereri river crossing, 3 miles S. of Melka Kunha, N.E. 
Kenya ; Kimmeridgian, Hereri Shales. 

Remarks. Dietrich founded the subgenus Tendagurium for equilateral Mesozoic 
Cardiidae lacking radial ornament. The question whether the type-species, Cardium 
propebanneianum, is specifically distinct from C. bannesianum is discussed below. 
There is no doubt that the two forms are closely related. In Europe this species 
appears to be confined to the Kimmeridgian. 

Protocardia (Tendagurium) propebanneiana (Dietrich) 

PI. 16, fig. 6 

x 933- Cardium [Tendagurium) propebanneianum Dietrich : 50, pi. 6, figs. 92, 93. 

Material. About 10 specimens. 

Locality and horizon. Tingutitinguti creek, Tendaguru, Tanganyika ; Upper 
Kimmeridgian, " Trigonia smeei " Bed. 

Remarks. Dietrich, when describing this species, discussed its possible identity 
with Cardium bannesianum Contejean, and concluded that it differs in its better 
developed posterior ridge and its less strongly convex pallial margin. These differ- 
ences, however, are not strongly marked. Dietrich mentions a specimen of C. pro- 
pebanneianum 80 mm. long, and the length of the largest of the specimens now 
recorded is 70 mm. These measurements are not greatly in excess of the maximum 
length of 65 mm. given by de Loriol for C. bannesianum. Dietrich mentions and 
illustrates a distinct pallial sinus in C. propebanneianum, whereas there is no sinus in 
C. bannesianum, but his figure has evidently been retouched to make the sinus 
obvious. Some of the specimens now recorded are internal moulds, but the pallial 
line is not clearly seen in any of them. The posterior adductor scar has, however, a 
well-marked anterior angle, and if this marks the point where the pallial line met the 
scar it is possible that a sinus may have been present and that the specific separation 
from C. bannesianum is justified. 

Superfamily ISOCARDIACEA [GLOSSACEA] 

Family CERATOMYOPSIDAE Cox 1964 

Genus CERATOMYOPSIS Cossmann 1915 

Ceratomyopsis basochiana (Defrance) 
PI. 17, figs. 7, 8a, b 

1822. Isocardia basochiana Defrance : 18. 

18226. Isocardia basochiana Defrance ; J. Sowerby, Part 7, " Isocardia " pi., fig. 4. 

1850a. Ceromya sarthacensis d'Orbigny : 336. 

1900. Isocardia striata d'Orbigny ; Miiller : 534, pi. 18, figs. \a, b (non d'Orbigny). 



FROM TANGANYIKA AND KENYA 107 

1903. Isocardia basochiana Defrance ; Bigot & Matte : 167. 

1910. Ceromya concentrica (Sow.) ; Dacque : 33, pi. 5, fig. 5 (non Sowerby sp.). 

1913. Ceromyopsis kiliani Rollier : 268, pi. 15, fig. 9. 

19156. Ceratomyopsis dassei Cossmann : 7, pi. 2, figs. 1-3. 

1924. Isocardia snbstriata Hennig : 67 (partim). 

1925. Ceromya sarthacensis d'Orbigny ; Cottreau : 9, pi. 37, figs. 7, 8. 
19376. Ceromyopsis substriata (Hennig) ; Cox : 202, pi. 16, fig. 4. 
i960. Ceromyopsis kiliani Rollier ; Joubert, pi. 11, figs. ia, b. 

Material. Three specimens. 

Localities and horizons. 2 miles E. of Magindu Station, Central Railway, 
Tanganyika ; Callovian. Hills S. of Rahmu-Melka Murri road, 13 miles W. of 
Rahmu, N.E. Kenya ; Callovian, Rukesa Shales. Kulong, 2 miles S.W. of Muddo 
Erri, N.E. Kenya ; Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Remarks. Defrance's description and Sowerby's figure of this species have been 
overlooked by most authors. Bigot & Matte have recorded that Defrance's holo- 
type was from the Callovian and there seems no doubt that the species is identical 
with the later described sarthacensis d'Orbigny, kiliani Rollier and dassei Cossmann, 
all from the Callovian of France. The specimen from the Callovian of Tanganyika 
figured by Muller as Isocardia striata and included by Hennig in his Isocardia sub- 
striata is characterized by its strongly coiled umbo, the tip of which is pointed up- 
wards so as to form the summit of the shell. The specimen from Tanganyika now 
recorded (the one figured by me previously under Hennig's name substriata) closely 
resembles it in this respect. These shells are now considered to fall within the range 
of variation of C. basochiana. 



Ceratomyopsis striata (d'Orbigny) 
PI. 17, fig. 9 

1822. Isocardia striata d'Orbigny : 104, pi. 2, figs. 7-9. 

1875. Isocardia striata d'Orbigny ; de Loriol : 56, pi. 13, figs. 35, 36. 

1897. Isocardia striata d'Orbigny ; Futterer : 602, pi. 21, figs. 3, 3a. 

1929. Ceromyopsis striata d'Orbigny, Futterer ; Weir : 32, pi. 3, fig. 8. 

1935a. Ceromyopsis striata (d'Orbigny) ; Cox : 188, pi. 19, fig. 10. 

i960. Ceromyopsis striata (d'Orbigny) ; Joubert, pi. 11, figs. 3a, b. 

Material. One specimen (no. L.92191). 

Locality and horizon. Hereri river crossing, 3 miles S. of Melka Kunha, N.E. 
Kenya ; Kimmeridgian, Hereri Shales. 

Remarks. It is not certain that this species differs morphologically from C. 
basochiana (Defrance), described in the same year, although it has been customary 
to draw a specific distinction between specimens from their respective horizons, 
Kimmeridgian and Callovian. The variability of C. striata is illustrated by the 
figures published by de Loriol (1875). 



108 JURASSIC BIVALVIA AND GASTROPODA 

Superfamily ARCTICACEA 

Family ARCTICIDAE Newton 1891 

Genus PRONOELLA Fischer 1887 

Pronoella pindiroensis sp. nov. 
PI. 17, figs. 12, 13, 14a, b, 15, 16, 17a, b 

Diagnosis. Of medium size (length of largest specimen 33 mm.), elongate-cunei- 
form, strongly inequilateral, height from one-half to two-thirds of length, beaks 
between anterior quarter and fifth of length ; some but not all specimens posteriorly 
rostrate, some strongly inflated, others only moderately so even when apparently 
uncrushed. Umbo not prominent, broadly rounded to obtusely angular, slightly 
incurved to prosogyrous beak. Postero-dorsal outline parasigmoidal to feebly and 
evenly convex and ventral margin posteriorly sinuate or feebly and evenly convex 
according to presence or absence of posterior rostrum ; posterior margin low, almost 
straight, oblique ; antero-dorsal outline slightly concave ; anterior margin broadly 
convex. Lunule moderately broad and deep, not distinctly bordered ; bordering 
ridges of escutcheon absent or ill-defined. An obtuse angulation, straight or para- 
sigmoidal according to presence or absence of posterior rostrum, and scarcely defined 
in some specimens, runs from beak to postero-ventral corner. Surface ornamented 
with irregular concentric threads or rugae which are present on all the anterior part 
but tend to disappear on the posterior part of the flank, and are absent from the 
posterior area. 

Holotype and paratypes. Holotype, no. LL.35135. There are numerous 
paratypes including nos. LL. 35136-40, but many are crushed. All ex B.P. Coll. 

Localities and horizon. Near site of Mandawa well no. 1, Tanganyika (type- 
locality) ; Lihimaliao creek, at a point near Mbaru creek, Mandawa area, Tangan- 
yika ; Bajocian (?), Pindiro Shales. 

Description. The description given in the diagnosis may be supplemented by 
an account of the dentition, which is that of a typical Pronoella. Right valve with 
an elongate posterior cardinal (36), obscurely bifid and almost parallel with postero- 
dorsal margin ; a triangular median cardinal (1) with its broad apex well separated 
from the beak and tapering anteriorly to be continued by a thin anterior lateral 
(Ai) ; a very thin, elongate anterior cardinal (3a) passing into an equally thin lateral 
(Aiii), the two separated by a very narrow recess from the adjacent margin ; and 
an elongate posterior lateral (Pi), separated by a recess from the margin : left valve 
with three cardinal teeth of which the posterior (46) is thin and elongate, lying along 
the lower margin of the ligamental nymph, the median (26) is stout, bifid, and in- 
clined backward from the beak, and the anterior [2d) is moderately stout and elon- 
gate and lies close to the antero-dorsal margin. 

Remarks. At first sight the specimens included in this species appear to belong 
to at least two different species, but there appears to be complete intergradation 
between specimens with a well-developed posterior rostrum and those with no ros- 



FROM TANGANYIKA AND KENYA 109 

trum. The rostrate specimens closely resemble the Hettangian species Cypricardia 
triangularis Terquem (1855 : 304, pi. 20, figs. 14, 14a), which may be a Prcnoella. 
Except for the small size the present species also much resembles Pronoella elongata 
Cox, from the Aalenian of England, type species of the subgenus Gythemon Casey, but 
its dentition resembles that of Pronoella s.str. (Casey 1952 : 145, text-fig. 34) rather 
than that of Gythemon (Casey : 151, text-fig. 47) in the relative strengths of the 
various hinge-teeth and in the anteriorly pointing direction of the tooth (1). 

Pronoella putealis sp. nov. 
PL 17, figs. 10, 11 

Diagnosis. Of small-medium size (length of holotype 21 mm.), cuneiform, 
moderately inequilateral, height two-thirds of length, beaks at anterior three- 
sevenths of length ; inflation apparently only moderate (the specimens have, how- 
ever, suffered compression). Umbo obtusely angular, moderately prominent, 
slightly incurved to prosogyrous beak. Antero-dorsal and postero-dorsal outlines 
concave, the latter forming an obtuse angle with the low, subvertical posterior mar- 
gin ; ventral margin of feeble to moderate convexity ; anterior margin broadly 
convex. No bordered lunule or escutcheon ; a thin, raised keel runs from the beak 
to the postero-ventral corner. Surface ornamented with fine, regular concentric 
threads, which are absent from the area dorsal to the keel. Hinge-teeth (seen only 
in fragments from well washings) as in typical Pronoella, but median cardinals (1) 
and (2fl) stouter in than P. pindiroensis. 

Holotype and paratypes. Holotype, no. LL.35141 ; two paratypes, including 
no. LL.35142. There are also several fragments from well sample washings. All 
ex B.P. Coll. 

Localities and horizon. Lihimaliao creek, at a point near Mbaru creek, 
Mandawa area, Tanganyika (type-locality) ; Mandawa well no. 6, Tanganyika (depths 
46-64 feet) : Bajocian (?), Pindiro Shales. 

Remarks. This species is smaller than P. pindiroensis and is also readily distin- 
guishable by its fine, regular concentric ornament. 

Pronoella kidugalloensis sp. nov. 
PL 18, figs. la, b 

Diagnosis. Of medium size (length 24-5 mm.), cuneiform, strongly inequilateral, 
height about three-quarters of length, beaks at anterior sixth of length, inflation 
moderately strong. Umbo broadly rounded, slightly incurved to the prosogyrous 
beak, its outline continuous posteriorly with the feebly convex, rather steeply 
sloping postero-dorsal outline of shell. Posterior margin low, subvertical ; ventral 
margin with very shallow sinus posterior to middle of its length, and merging anterior- 
ly in a broad curve with the feebly convex, prosocline anterior margin ; antero- 
dorsal outline a little excavated. Lunule broad and deep ; escutcheon broad but 



no JURASSIC BIVALVIA AND GASTROPODA 

shallow, its bordering ridges rather obscure ; diagonal ridge distinct near umbo but 
dying out before reaching postero- ventral corner of shell. Ornament consisting of 
narrow and rather irregularly spaced concentric folds (obliterated by erosion on 
part of surface of holotype). Internal characters unknown. 

Holotype. No. LL.35I43, ex B.P. Coll. There is also a fragment of a second 
specimen. 

Locality and horizon. i\ miles N.N.W. of Kidugallo, Central Railway, 
Tanganyika ; Bajocian. 

Remarks. This species is referred to Pronoella on account of its general resemb- 
lance to P. pindiroensis sp. nov., from which it differs in its less elongate but more 
strongly inequilateral form, its broader lunule, and its more strongly ribbed surface. 



Genus ANISOCARDIA Munier-Chalmas 1863 

Anisocardia arkelli sp. nov. 
PI. 18, figs. 5«, b 

Specific name. After the late Dr. W. J. Arkell. 

Diagnosis. Of medium size (length of largest specimen 17-5 mm.), subtrigonal, 
inequilateral, length well exceeding height, beaks at about anterior third of length ; 
inflation strong. Umbo prominent, narrowly rounded, well incurved, with beak 
strongly prosogyrous. Postero-dorsal outline feebly convex, steeply sloping ; 
posterior margin low, sharply convex ; ventral margin of moderate and even con- 
vexity ; anterior margin narrowly rounded, with anterior extremity low, at about 
one-quarter of shell height ; antero-dorsal outline strongly concave. No distinct 
posterior umbonal ridge present. 

Holotype and paratypes. Holotype, no. LL.35051. Four paratypes, nos. LL. 

35052-55- 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This species bears some resemblance to A. gibbosa (Minister) (Cox, 
1947 : 161, text-figs. 29a, b), from the European Bajocian, but is smaller and less 
gibbose. 

Anisocardia didimtuensis sp. nov. 
PI. 18, fig. 4 

Diagnosis. Of medium size (length of holotype 20-8 mm.), subtrigonal, inequi- 
lateral, length well exceeding height, beaks at about anterior third of length ; in- 
flation strong ; umbo prominent, narrowly rounded, very strongly incurved, with 
beak strongly prosogyrous. Postero-dorsal outline strongly convex near umbo, 
slightly concave more posteriorly, steeply sloping, forming an obtuse angle with short, 



FROM TANGANYIKA AMD KENYA m 

subvertical posterior margin ; ventral margin of even and very feeble convexity ; 
anterior margin abruptly rounded, anterior extremity low, at about one-fifth of shell 
height. No well-defined posterior umbonal ridge present. 

Holotype. No. L. 35056. The only specimen. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This species appears to be distinct from A. arkelli, with which it 
occurs associated. The umbo is more elevated than in that species, the beak 
considerably more incurved and strongly prosogyrous, and the antero-dorsal outline 
more excavated. The slight concavity of the postero-dorsal outline, moreover, is 
not seen in A. arkelli. 

A specimen from the Upper Lias of Madagascar figured by Thevenin (19086 : 29, 
text-fig. 24) as Gresslya cf. pingnis Agassiz is not a Gresslya, but an Anisocardia which 
differs from the species now described in its rather higher anterior extremity and its 
less strongly prosogyrous beak. Anisocardia fullonica Cox (1947 : 164, text-figs. 
34a, b ; pi. 9, fig. 73), from the Lower Bathonian (Fuller's Earth Rock) of southern 
England, closely resembles the form now described but is more tumid and has a less 
evenly convex ventral margin. 



Anisocardia ayersi sp. nov. 
PI. 18, figs. 6a, b 

Specific name. After Mr. F. M. Ayers, of the Kenya Geological Survey, who 
first discovered the beds at Didimtu. 

Diagnosis. Of medium size (length of holotype 20-5 mm.), subovate, length 
slightly exceeding height, beaks at about anterior quarter of length, inflation moder- 
ate. Umbo not prominent, narrowly rounded in outline, moderately incurved and 
prosogyrous. Postero-dorsal outline feebly convex, sloping gently, and forming an 
obtuse angle with the straight, slightly oblique posterior margin ; ventral margin of 
moderate and even convexity ; antero-dorsal outline slightly concave ; anterior 
margin broadly rounded, anterior extremity at about one-third of shell height. No 
distinct posterior umbonal ridge present. 

Holotype. No. LL. 35057. The only specimen. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This species bears some resemblance to A. stamfordensis Cox (1947 : 
160, text-figs. 24a, b ; pi. 9, fig. 72), Bajocian of England, but its umbo is less promin- 
ent, it lacks a posterior umbonal ridge, and its ventral margin is not flattened poste- 
riorly, as in that species. 



112 JURASSIC BIVALVIA AND GASTROPODA 

Anisocardia minima (J. Sowerby) 
PL 18, fig. 8 

1821a. Isocardia minima J. Sowerby : 171, pi. 295, fig. 1. 

1934a. Anisocardia minima (J. Sowerby) ; Arkell : 275, pi. 36, figs. 8-1 1. 

1947. Anisocardia minima (J. Sowerby) ; Cox : 170, text-figs. 43a, b. 

Material. One specimen (no. L.92120). 

Locality and horizon. Hills S. of Rahmu-Melka Murri road, 13 miles W. of 
Rahmu, N.E. Kenya ; Callovian, Rukesa Shales. 

Remarks. This specimen, about 21 mm. long, is not distinguishable from English 
specimens of this well-known species, discussed in my 1947 paper. The range of the 
species in Europe is from Upper Bajocian to Callovian or possibly Oxfordian. 

Anisocardia kinjeleena sp. nov. 
PI. 18, fig. 3 

Diagnosis. Shell of medium size for the genus (length of holotype 17-5 mm.), 
subquadrate, with height little less than length ; inflation rather feeble. Umbo 
projecting slightly above postero-dorsal outline, and well incurved to strongly pro- 
sogyrous beak, which lies at about anterior quarter of length of shell. Posterior 
margin straight, forming a rounded-off angle which is only slightly greater than a 
right angle with straight postero-dorsal outline and a slightly less well-defined angle 
with moderately and symmetrically convex ventral margin. Anterior end of shell 
rather low, with strongly convex margin ; antero-dorsal outline well excavated. 
Diagonal ridge sharp, presenting an upward-facing convexity along its entire length, 
and delimiting a strongly concave postero-dorsal area. 

Holotype and paratypes. Holotype, no. L.51938. Three paratypes. 

Localities and horizons. Kinjele, 5 miles W. of Mtapaia, N. of Tendaguru, 
Tanganyika (type-locality) ; Upper Kimmeridgian, Indogrammatodon Bed. Kin- 
dope valley, N.N.W. of Tendaguru ; Upper Kimmeridgian, Nerinella Bed. 

Remarks. This species is referred to Anisocardia rather than to Opis as the 
specimens have no trace of concentric ornament, which is usually visible even on 
internal moulds of the latter genus. Its subquadrate form and high postero-dorsal 
angle serve to distinguish it from any species of Anisocardia described previously. 



Genus EO TRA PEZI UM Douville 1913 

Eotrapezium ? africanum sp. nov. 
PI. 18, figs. 7a, b 

Diagnosis. Of medium size (length of holotype 32-3 mm.), subrectangular, 
elongate, inequilateral, beaks at anterior quarter of length, inflation moderate. 
Umbonal outline obtuse, umbones slightly incurved ; postero-dorsal margin almost 



FROM TANGANYIKA AND KENYA 113 

straight, subhorizontal, forming an obtuse angle with the straight, slightly oblique 
posterior margin ; ventral margin almost straight ; antero-dorsal outline strongly 
concave ; anterior margin strongly convex. An obtusely rounded ridge, curved 
with an upward-facing convexity, runs from the umbo to the postero-ventral corner 
in each valve. Pallial line entire. 

Holotype. No. LL. 35058. There are also two very imperfect specimens. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. The specimens are internal moulds and details of their hinge-structure 
cannot be ascertained. The species is referred, with a query, to Eotrapezium because 
its subrectangular outline resembles that of some specimens of the Lower Liassic 
type species, Mesodesma germari Dunker, such as those from Portugal figured by 
Boehm (1901, pi. 10, figs. 6, 7). Alternatively, it could conceivably belong to the 
Astartidae, but its strongly excavated antero-dorsal outline and greater inflation 
distinguish it from known species of the astartid subgenus Leckhamptonia, in which 
the rectangular outline of the shell is somewhat similar. No closely comparable 
species has been described previously from the Upper Lias. 

Eotrapezium ? thompsoni sp. nov. 
PI. 18, figs. 2a, b 

Specific name. After Mr. A. O. Thompson, of the Kenya Geological Survey, 
collector of the type material. 

Diagnosis. Of small-medium size (length 17 mm.), trapeziform, inequilateral, 
length not greatly exceeding height, beaks at anterior quarter of length ; inflation 
rather weak (but holotype somewhat crushed). Umbonal outline obtuse, umbones 
scarcely incurved ; postero-dorsal outline feebly convex, subhorizontal, forming an 
obtuse angle with the straight, slightly oblique posterior margin ; ventral margin of 
feeble convexity, diverging slightly from postero-dorsal outline in a posterior direc- 
tion ; antero-dorsal outline moderately concave ; anterior margin strongly convex. 
An obtusely rounded ridge, curved with an upward facing convexity, runs from the 
umbo to the postero-ventral corner. Surface ornamented with concentric threads. 

Holotype. No. LL. 35061. There is also one very imperfect specimen. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya. 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This species bears a general resemblance to Eotrapezium? africanum, 
described above, but differs in its much shorter form. 

Eotrapezium ? kenti sp. nov. 
PI. 18, figs, ga, b, 10a, b 

Specific name. After Dr. P. E. Kent, of the British Petroleum Company, Ltd. 
Diagnosis. Shell of medium size (length of holotype c. 27 mm.), ovate-cuneiform, 



ii4 JURASSIC BIVALVIA AND GASTROPODA 

height about four-fifths of length, inflation moderate. Umbo broadly rounded, 
incurved to the moderately prosogyrous beak, which is situated at the anterior 
quarter of the length of the shell ; outline of umbo continuous with the evenly 
convex postero-dorsal outline, which slopes at a fairly steep angle to the low, abruptly 
rounded posterior extremity. Ventral margin feebly convex, continuous with 
strongly and evenly convex anterior margin ; antero-dorsal outline well excavated. 
Lunule shallow, not bordered ; escutcheon ridge as well as ridge running diagonally 
from umbo to postero-ventral corner weakly defined. Surface ornamented in 
later growth-stages with narrow, irregular concentric undulations. 

Hinge-teeth of right valve consisting of elongated outer posterior cardinal (4^) 
adjacent to nymph, a strong, well elongated inner posterior cardinal (2 of Douville\ 
2b 2 of Casey) sloping back from the beak, an equally strong and similarly well elon- 
gated anterior cardinal (2b 1 of Casey) diverging at obtuse angle from inner posterior 
cardinal, and an anterior lateral Aii, which is separated from the anterior cardinal 
by a distinct constriction. 

Holotype and paratypes. Holotype, no. LL.35144 ; two paratypes, including 
no. LL.35145 ; all ex B.P. Coll. 

Locality and horizon. Magole, 5 miles N.W. of Kidugallo, Tanganyika ; Bajo- 
cian. 

Remarks. As the dentition of the right valve is unknown it is not possible to 
assign this species to any genus with complete confidence. The hinge of the left 
valve agrees with that of the type-species of Eotrapezium, Mesodesma germari Dun- 
ker, from the Lower Lias, as figured by Boehm (1901 : 238, fig. 19) and by Douville 
(1913 : 455, fig. 38), in the elongation and broad divergence of the two inner cardinal 
teeth, but the anterior of these passes without any interruption into the anterior 
lateral in E. germari and in two other species of Eotrapezium figured by Douville 
(1913, figs. 40, 42), whereas it is separated from it by a distinct constriction in the 
species now described. The dentition of the left valve of this species also bears some 
resemblance to that of Anisocardia (Antiquicyprina) loweana (Morris & Lycett), 
from the English Bathonian, as figured by Casey (1952 : 151, fig. 49), but the two 
inner cardinal teeth are much more elongated than in the species in question. 

Family NEOMIODONTIDAE Casey 1955 

Genus EOMIODON Cox 1935 

Eomiodon baroni (Newton) 
PI. 18, fig. 11 

1889. Astarte? baroni Newton : 336, pi. 14, figs. 9-1 1. 

1936. Astarte baroni Newton ; Besairie : 121, pi. 7, figs. i, 2. 

Material. Several specimens. 

Localities and horizons. Quarries N.N.E. of Ngerengere, Central Railway, 
Tanganyika ; Bajocian (?). 6 miles N.W. of Kidugallo, Tanganyika ; Bajocian 
(B.P. Coll.). 



FROM TANGANYIKA AND KENYA 115 

Remarks. Newton's holotype of Astarte? baroni, from Madagascar, is so ill- 
preserved that when describing the specimens from India (Cox 1935ft : 7, pi. 1, figs. 
17-19) upon which I founded the genus and species Eomiodon indicus I did not 
recognize their generic affinity with it. Examination of further material from 
Madagascar has left me with no doubt on this point. The two forms are similar in 
size and outline, but E. indicus is much more strongly inflated than any specimens of 
the Madagascan species which I have examined, and it is doubtful if they should be 
placed in synonymy. 

Of the specimens now recorded fom Tanganyika, those from Ngerengere are quite 
typical. Those from the locality near Kidugallo, only two in number, are relatively 
small, the larger being only 19 mm. long, and the relatively wide-spaced concentric 
ridges of the earlier growth-stages are replaced by closely spaced ridges at a shorter 
distance from the umbo than in typical specimens. They could possibly belong to a 
distinct species or subspecies, but there is insufficient material for a decision to be 
reached on this point. 



Eomiodon tanganyicensis sp. nov. 
PI. 18, figs. 12a, b, 13 

Diagnosis. Of medium size (length of holotype c. 27 mm.), cuneiform, moderately 
inflated. Umbones anteriorly placed but not quite terminal, well incurved to the 
strongly prosogyrous beaks. Postero-dorsal outline strongly convex anteriorly, less 
convex posteriorly, sloping to the low, subangular posterior extremity of the shell. 
Ventral margin strongly convex, merging anteriorly with the convex anterior mar- 
gin ; antero-dorsal outline slightly concave. Escutcheon not distinctly bordered 
by a ridge. Surface of shell without marked concentric ornament. 

Cardinal teeth consisting, in left valve, of stoutly triangular, anteriorly directed 
anterior tooth (2b) very close to antero-dorsal margin, and of a quite strong, elongate 
posterior tooth (4ft) widely divergent from 2b ; in right valve, of stout, triangular, 
mesially placed tooth (3ft) and narrow, weak anterior tooth (3a). Right valve with 
strong, lamelliform posterior lateral tooth (Pi) and a weaker, lamelliform anterior 
lateral (Ai), each separated from shell margin by a recess for the reception of a lateral 
tooth formed by a projection from the corresponding part of margin of left valve. 

Holotype and paratypes. Holotype, no. LL.7215. About 20 paratypes. 

Locality and horizon. Quarries N.N.E. of Ngerengere, Central Railway, Tanga- 
nyika ; Bajocian (?). 

Remarks. The specimens are encrusted with fine sandy material, but their lack 
of concentric ornament appears to be an original feature and to distinguish them 
from E. baroni. The lack of an angular ridge bordering an escutcheon is another 
point of difference. They are less gibbose than E. baroni, but it is not possible to 
say if this difference is entirely due to the compression which most of them have 
undergone. Their dentition is that of a typical Eomiodon. 



n6 JURASSIC BIVALVIA AND GASTROPODA 

Eomiodon dinosaurianum sp. nov. 
PI. 18, figs. 15a, b, 16a, b 

1933. Cyrena sp. ; Dietrich : 46, pi. 8, fig. 125 ; ? pi. 11, fig. 147. 

Diagnosis. Shell small (usual length c. 12 mm.), trigonally ovate, variable in 
proportions but always longer than high, subequilateral to moderately inequilateral, 
with beaks lying between a position slightly posterior to median and the anterior 
quarter of the length ; inflation moderate (most specimens, however, are crushed). 
Umbo broadly rounded, slightly incurved to the moderately prosogyrous beak, its 
outline continuous with straight postero-dorsal outline of shell ; postero-dorsal 
outline sloping at a moderately steep angle to meet the usually short, straight 
posterior margin in an obtuse angle ; ventral margin convex to a variable extent, 
merging in an even curve with the strongly convex anterior margin ; antero-dorsal 
outline slightly concave. Escutcheon moderately wide, bordered by well-defined 
ridges ; lunule somewhat excavated, not bordered. A rather obscure diagonal ridge 
runs from the umbo to postero-ventral corner of shell. Ornament consisting of thin 
concentric ridges which fade away at a variable distance from the umbo, so that 
later growth-stages are smooth in all full-grown specimens ; ridges separated by 
much broader intervals. 

Holotype and paratypes. Holotype, no. L. 53322. There are also numerous 
paratypes. 

Locality and horizon. Tendaguru, Tanganyika ; excavation in Upper Kim- 
meridgian, dinosaur beds. 

Remarks. The specimens are preserved in fine-grained buff-coloured sandstone. 
The great amount of variation which they show appears to be largely due to original 
differences in shape, although many have suffered distortion and compression in 
fossilization. The species is not closely comparable to any previously described 
from the Upper Jurassic. E. nortonensis (Cox) (1944& : III, text-fig. 4c), from the 
Lower Bathonian of England, is of about the same size as the East African species, 
but differs in its cuneiform and more elongate shape. 



Eomiodon namgaruensis sp. nov. 
PL 18, figs. 14a, b 



Diagnosis. Rather large for the genus (length of holotype 49 mm.), ovate- 
cuneiform, inequilateral, height about four-fifths of length, beaks at anterior fifth 
of length ; inflation strong. Umbo prominent, very broadly rounded, well incurved 
to the strongly prosogyrous beak. Postero-dorsal outline pronouncedly parasigmoi- 
dal, rather steep, forming an obtuse angle with the low, straight, oblique posterior 
margin ; ventral margin strongly convex ; antero-dorsal outline strongly concave ; 
anterior margin broadly convex. Escutcheon moderately wide, well impressed, 
bordered by sharp ridges ; lunule broad, cordate, well impressed, smooth, also 
bordered by a ridge in each valve. No distinct ridge runs from the beak to the 



FROM TANGANYIKA AND KENYA 117 

postero-ventral corner of the shell. Early growth-stages ornamented with narrow, 
regular concentric ridges of which those farthest from the umbo are about 1 mm. 
apart ; remainder of shell with only irregular concentric rugae. 

Holotype and paratype. Holotype, no. LL.35146 ; one broken paratype. 
Both ex B.P. Coll. 

Locality and horizon. About 1 mile E.S.E. of Uleka, Mavudyi-Namgaru area, 
Tanganyika ; Jurassic (stage uncertain). 

Remarks. The dimensions of this shell, which has the unmistakable external 
characters of Eomiodon, exceed those of any previously known Jurassic species of the 
genus, but are less than those of E. libanotica (Fraas) (Vokes, 1946 : 172, pi. 5, figs. 
1-12, as Protocyprina libanotica) from the Aptian of the Lebanon. 

Subgenus AFRICOMIODON nov. 

Diagnosis. Well inflated, with anteriorly placed, prominent, strongly proso- 
gyrous and incurved umbones. Escutcheon broader than in Eomiodon s.str. and 
bordered by ridges which are not so well defined as in that group ; in each valve one 
cardinal tooth (26 in the left, 36 in the right) is stoutly triangular, but remaining 
cardinals only feebly developed. Anterior lateral (Aii) in left valve and posterior 
lateral (Pi) in right valve strongly developed, remaining laterals weak. 

Type species. Eomiodon (Africomiodon) cutleri sp. nov. 

Remarks. This new subgenus resembles Eomiodon s.str. in the general arrange- 
ment of the hinge teeth and in the presence of evenly spaced concentric ridges which 
are confined to earlier growth stages. It is distinguished by the very different shape 
and strong inflation of the shell and by the weakness of all the teeth except the four 
mentioned. 

Eomiodon (Africomiodon) cutleri sp. nov. 
PI. 18, figs. 17, 18a, b 

Specific name. After the late W. E. Cutler, the first leader of the British Museum 
East Africa Expedition. 

Diagnosis. Shell of medium size, with characteristic asymmetrical outline due 
to pronounced postero-dorsal angle and rather protruding, very anteriorly placed, 
prosogyrous umbones ; height (20-5 mm. in holotype) slightly exceeding length in 
most specimens. Postero-dorsal outline convex, gently sloping, forming rather pro- 
nounced, obtuse angle with feebly convex posterior margin ; this merges into the 
strongly and evenly convex ventral margin which is continued by the equally con- 
vex anterior margin, the two forming almost a semicircle ; antero-dorsal outline 
strongly excavated. The evenly spaced, well separated concentric ridges present 
in early growth stages (where they are particularly prominent on the posterior part 
of the surface) soon give way to the unevenly arranged concentric threads and rugae 
which occupy the greater part of the surface. Dentition as described in the sub- 



1 18 JURASSIC BIVALVIA AND GASTROPODA 

generic diagnosis (the indistinctness of all the teeth except 26, 3a, Aii and Pi may be 
partly due to the fact that it has been necessary to develop out the hinge region from 
a hard limestone matrix in the specimens studied, but these teeth must have been 
quite weak originally). 

Holotype and paratypes. Holotype, no. L.51995 ; numerous paratypes. 

Localities and horizons. Tingutitinguti creek (type-locality) and Kipande, 
Tendaguru, Tanganyika ; Upper Kimmeridgian, " Trigonia smeei " Bed. Scarp at 
Kindope, N. of Tendaguru ; Upper Kimmeridgian, Nerinella Bed. 

Remarks. Notwithstanding some external similarity to specimens from the 
dinosaur beds of Tendaguru figured by Hennig (1914ft, pi. 14, figs. la-i) as Cyrena sp., 
the hinge structure of the shells now described differs considerably from that of the 
two valves represented in Hennig's pi. 14, figs. 2a, b. The form figured by Hennig 
does not seem to be represented in the material examined by the present writer. 
The Cyprina sp. of Dietrich (1933 : 46, pi. 8, fig. 125 ; pi. 11, fig. 147) seems to be 
the Eomiodon dinosaurianum of the present memoir. 

Superfamily TELLINACEA 

Family TANCREDIIDAE Meek 1864 

Genus TANCREDIA Lycett 1850 

Tancredia sp. "A" 

PI. 19, fig. 2 

Material. One specimen (no. L. 93625). 

Locality and horizon. Korkai Hammassa, 19 miles E. of Takabba, N.E. 
Kenya ; Oxfordian, Golberobe Beds. 

Description. This specimen is the internal mould of the right valve of a moderate- 
ly elongate Tancredia, 22-3 mm. long and 11 mm. high. The umbo is slightly anterior 
to mid-length, and just in front of it there is a slight concavity of the antero-dorsal 
outline, which slopes at a rather gentle angle to the blunt anterior extremity of the 
shell. It is close to the Tancredia from the Oxfordian of Cordebugle (Calvados) 
figured by Chavan (1952, pi. 4, figs. 48-50) under the name Corbicella (Corbicellopsis) 
antissiodorensis (Cotteau), but its anterior end is more tapering and sharply rounded 
than in that species. It is also very similar to the English Bathonian species T. 
extensa Lycett, figured under the name T. axiniformis (Phillips) by Morris & 
Lycett (1855 : 93, pi. 12, fig. 7 ; pi. 13, figs. 6a, b), but its umbo is situated in a 
slightly more anterior position. 

Tancredia sp. " B " 
PI. 19, fig. 3 

Material. One specimen (no. L. 93614). 

Locality and horizon. Ogar Wein, 17 miles N.W. of Wergudud, N.E. Kenya ; 
Oxfordian, Golberobe Beds. 



FROM TANGANYIKA AND KENYA 119 

Description. This specimen is the internal mould of the right valve of a moder- 
ately elongate Tancredia, 20-5 mm. long and n mm. high. The umbo lies at about 
the posterior two-fifths of the length, and the slightly concave antero-dorsal outline 
slopes rather steeply to the abruptly rounded anterior extremity of the shell. The 
specimen is very much like the English Bajocian and Bathonian species T. angulata 
Lycett, as figured by Morris & Lycett (1855 : 94, pi. 12, fig. 8 ; pi. 13, figs, ga, b). 

Tancredia manderaensis sp. nov. 
PI. 19, fig. 1 

Diagnosis. Shell of medium size (length of holotype 22 ram., height 13 mm.), 
moderately elongated, subequilateral. Antero-dorsal outline concave, sloping gently 
to the rather sharply rounded anterior extremity of the shell. Ventral margin of 
moderate convexity, the more strongly upcurved anteriorly. Posterior margin 
weakly convex, slightly prosocline, forming an obtuse angle with the almost horizontal 
postero-dorsal margin. Posterior diagonal ridge strong, delimiting a narrow, con- 
cave posterior area. 

Holotype. No. LL.35190, consisting of the internal and external moulds of a 
left valve. There is also a distorted specimen, possibly of the same species, in the 
same piece of rock. 

Locality and horizon. Matasafara, 15 miles W. of Mandera, N.E. Kenya ; 
uppermost Jurassic, Gudediye Beds. 

Remarks. Compared with the " Tancredia sp.A " of the Golberobe Beds (Oxfor- 
dian) of N.E. Kenya and with the Tancredia from the Oxfordian of Cordebugle, 
Calvados, France, figured by Chavan (1952 : 106, pi. 4, figs. 48-50) as Corbicella 
(Corbicellopsis) autissiodorensis (Cotteau), this species is a little less elongated. It 
is very close to the European Bathonian species T. extensa Lycett, as figured (under 
the name T. axiniformis (Phillips)) by Morris & Lycett (1855, pi. 12, fig. 7 especially), 
but has a more strongly convex ventral margin. 

Family QUENSTEDTIIDAE Cox 1929 

Genus QUENSTEDTIA Morris & Lycett 1855 

Quenstedtia saggersoni sp. nov. 
PL 19, figs. 4, 6 

Specific name. After Mr. E. P. Saggerson, of the Kenya Geological Survey. 

Diagnosis. Of medium size, oblong, well elongated, with length (35 mm. in 
holotype) exceeding twice the height ; only slightly inequilateral, with broadly 
rounded, slightly protruding umbo just anterior to mid-length. Posterior margin 
feebly convex, a little oblique in its general direction, joining the straight, parallel 
postero-dorsal and ventral margins in even curves ; anterior margin strongly and 
evenly convex. 



120 JURASSIC BIVALVIA AND GASTROPODA 

Holotype and paratype. Holotype, no. L.93600. One paratype, no. L.93636. 

Localities and horizon. Ogar Wein, 17 miles N.W. of Wergudud, N.E. Kenya 
(type-locality) ; Korkai Hammassa, 19 miles E. of Takabba, N.E. Kenya ; both 
Oxfordian, Golberobe Beds. 

Remarks. This species is rather closely comparable to Q. elongata Hudleston, an 
English Oxfordian species figured by Arkell (1934a : 298, pi. 40, figs. 6, 7), but is not 
quite so inequilateral. It is more elongate and less inequilateral than Q. laevigata 
(Phillips), another Oxfordian species figured by Arkell (1934a : 296, pi. 40, figs. 4, 5). 

Quenstedtia jouberti sp. nov. 
PI. 19, fig. 5 

i960. Quenstedtia sp ; Joubert, pi. 10, fig. 1. 

Specific name. After Mr. P. Joubert, of the Kenya Geological Survey, collector 
of the holotype. 

Diagnosis. Moderately large for the genus (length of holotype 60 mm. -f), 
rather pronouncedly inequilateral ; umbones broadly rounded, projecting very 
slightly above dorsal margins, and placed at anterior third of length. Postero-dorsal 
margin straight, forming an obtuse angle with posterior margin, which merges with 
ventral margin in a broad curve ; ventral margin straight, diverging slightly from 
postero-dorsal margin in a posterior direction ; antero-dorsal outline moderately 
excavated ; anterior margin (damaged in holotype) apparently evenly rounded. 
An obtuse ridge runs from the umbo to the postero- ventral corner of the shell. 

Holotype. No. L. 92213. The only specimen. 

Locality and horizon. N. of Figfirya, northern Raiya hills, N.E. Kenya ; 
Upper Kimmeridgian, Dakacha Limestones. 

Remarks. This species is less elongate and more strongly inequilateral than Q. 
gortanii Venzo (1949 : 159, pi. 16, fig. 27), the most closely comparable of the five 
representatives of the genus described by this author from the late Jurassic beds at 
Cud Finagubi, in northern Kenya. It is much more inequilateral than the English 
Portlandian species Q. portlandica Cox (1929 : 191, pi. 6, figs. 5, 6). 

Superfamily MYACEA 

Family CORBULIDAE Gray 1823 

Genus CORBULA Bruguiere 1797 

Corbula didimtuensis sp. nov. 
PI. 19, figs. 10, ii«, b, c 

Diagnosis. Moderately large for the genus (length of largest specimen 24 mm.), 
subrectangular with a triangular tendency, very slightly inequilateral, not rostrate 
posteriorly ; height two-thirds to three-quarters of length ; beaks slightly anterior 



FROM TANGANYIKA AND KENYA 121 

to median ; inequivalve, right valve larger but only slightly more inflated than left ; 
most inflated part of each valve lying anterior to umbones. Right umbo rather 
broadly rounded, prominent, higher than more narrowly rounded umbo of left valve ; 
both are slightly incurved to the feebly prosogyrous beaks. Umbonal outline in 
right valve rising slightly above the straight, gently inclined postero-dorsal margin, 
which forms an acute angle with the slightly oblique posterior margin ; the latter 
curves round below to merge with the straight or feebly convex ventral margin. 
Antero-dorsal outline very feebly concave, steeply sloping ; anterior margin rounded, 
feebly convex. In right valve a narrow and very shallow sulcus runs in some speci- 
mens from the umbo to meet the ventral margin near its posterior extremity, while 
a second narrow sulcus, scarcely perceptible, runs down the posterior slope from 
behind the umbo to the point where the posterior and ventral margins meet. In 
left valve a rounded-off anterior beak ridge is present in early growth-stages. There 
is no impressed lunule in either valve. Both valves are ornamented with fine and 
irregular concentric threads, and irregular concentric undulations may also be 
present ; radial ornament lacking. 

Holotype and paratypes. Nos. LL.35073 and LL.35074-75 respectively, three 
specimens in all. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This large Corbitla does not closely resemble any Jurassic species 
hitherto described. It is rather like the well-known Eocene species C. gallica 
Lamarck, differing in its flatter ventral margin and somewhat smaller size. 



Corbula mandawaensis sp. nov. 
PI. 19, figs. 7a, b, 8a, b 

Diagnosis. Of medium size for the genus (length of holotype 5-6 mm., of largest 
specimen c. 9-0 mm.), trigonally ovate, rather strongly inequilateral, carinate but 
not rostrate posteriorly, height two-thirds of length, beaks at anterior third to 
quarter of length ; probably very slightly inequivalve (all specimens retaining both 
valves in position have, however, suffered distortion by compression) ; inflation 
moderate. In both valves, umbo broadly rounded, well incurved to the rather 
strongly prosogyrous beak ; umbonal outline rising well above the straight, gently 
inclined postero-dorsal margin, which forms an obtuse angle with the very oblique, 
straight posterior margin ; ventral margin evenly and rather feebly convex ; antero- 
dorsal outline slightly concave, steeply sloping ; anterior margin of moderate con- 
vexity ; a well-marked, sigmoidal diagonal ridge delimits a flattened or concave 
posterior area. Ornament consisting of fine, regular concentric threads present on 
the flank but not on the posterior area. 

Holotype and paratypes. Holotype, no. LL.35148 ; several paratypes, in- 
cluding nos. LL.35147, LL.35149, but many are imperfect or crushed. All ex B.P. 
Coll. 



122 JURASSIC BIVALVIA AND GASTROPODA 

Locality and horizons. Mandawa well no. 6, Tanganyika, at depths 46-48 feet 
(holotype), 48-50 feet, 50-52 feet, 52-54 feet, 54-56 feet, 56-58 feet, 58-60 feet, 
62-64 f eet > 64-66 feet, 70-72 feet ; Bajocian (?). 

Remarks. In the two French Bajocian species C. aglaia d'Orbigny and C. alimena 
d'Orbigny (types figured by Thevenin, iqua, pi. 26, figs. 34 and 36, 37 respectively), 
which may be synonymous with one another, the truncated posterior end of the shell 
is lower and the concentric ornament less regular than in the new species. 

Corbula tanganyicensis sp. nov. 
PL 19, figs, ga, b, 12a, b, c, d 

Diagnosis. Rather small (length of largest specimen c. 5 mm.), trigonally ovate, 
slightly inequilateral, some specimens subrostrate posteriorly, height two-thirds of 
length, beaks situated between anterior third and middle of length ; very slightly 
inequivalve, left valve slightly the lower, with its ventral margin overlapped by that 
of right valve, but scarcely differing from the latter in its moderately strong inflation. 
In both valves, umbo broadly rounded, well incurved to the rather strongly proso- 
gyrous beak ; umbonal outline rising well above the straight, gently inclined, and 
in some specimens relatively short postero-dorsal margin ; ventral margin strongly 
convex anteriorly, flattened or sinuate posteriorly ; antero-dorsal outline slightly 
concave, steeply sloping ; anterior margin of varying convexity ; a well-defined, 
sigmoidal diagonal ridge delimits a concave posterior area. Ornament consisting of 
fine, regular concentric riblets present on flank but not on posterior area. 

Holotype and paratypes. Holotype, no. LL. 35150 ; several paratypes, in- 
cluding no. LL.35151. All ex B.P. Coll. 

Locality and horizons. Mandawa well no. 7, Tanganyika, at depths 3760-3770 
feet and 4510-4520 feet (holotype) ; Bajocian (?). 

Remarks. This species is smaller and slightly more gibbose than C. mandawaen- 
sis, and also differs in its narrower, commonly rostrate posterior extremity and in its 
rather coarser concentric ornament. 

Corbula pindiroensis sp. nov. 
PL 19, figs. 14a, b, c, 15a, b 

Diagnosis. Of medium size for the genus (length of largest specimen c. 13 mm.), 
trigonally ovate, slightly to moderately inequilateral, not rostrate posteriorly, height 
about two-thirds of length, beaks at anterior two-fifths to third of length ; rather 
strongly inflated, apparently sub-equivalve (all specimens, however, have suffered 
some distortion by compression). In both valves, umbo very broadly rounded, well 
incurved to the moderately prosogyrous beak ; umbonal outline rising only slightly 
above the feebly concave postero-dorsal outline, which forms a slightly obtuse angle 
with the straight, low, slightly oblique posterior margin ; ventral margin of rather 
strong convexity, straightened and upturned at its posterior end ; anterior margin 



FROM TANGANYIKA AND KENYA 123 

strongly convex ; antero-dorsal outline slightly concave ; a sharply angular, 
sigmoidal diagonal ridge delimits a narrow, concave posterior area. Ornament of 
strong, unequal, unevenly arranged concentric riblets and threads on flank, and finer 
growth threads on posterior area. 

Holotype and paratypes. Holotype, no. LL.35152 ; about 16 paratypes, in- 
cluding no. LL. 35153, and mostly very imperfect. All ex B.P. Coll. 

Locality and horizons. Pindiro well no. i, Tanganyika, at depths 162-166 feet, 
166-170 feet (holotype), 170-174 feet, 174-178 feet, 178-180 feet, 194-198 feet, 
250-254 feet ; Bajocian (?). 

Remarks. This species does not closely resemble any corbulid previously 
described from the Middle Jurassic. The English Bathonian form C. attenuata 
Lycett (1863 : 62, pi. 37, figs. 6, 6a) is more elongate, with a broader and less prom- 
inent umbo. 

Corbula kidugalloensis sp. nov. 
PI. 19, figs. 17a, b, c 

Diagnosis. Of medium size for the genus (length of holotype 1 1 -2 mm.) , pyriform, 
with a short posterior rostrum, subequivalve, gibbose ; height equal to about three- 
quarters of length. Umbones broadly rounded, prominent, almost median in 
position, well incurved to the prosogyrous beaks. Lunular region well impressed. 
Antero-dorsal outline slightly concave, sloping steeply to the evenly rounded anterior 
end of the shell. Ventral margin asymmetrically and rather strongly convex, with 
a small sinus (indicated by the growth-lines, this part of the actual margin being a 
little imperfect) at the beginning of the pointed rostrum. Postero-dorsal outline 
almost straight, sloping steeply ; posterior umbonal ridges weak, sigmoidally curved. 
Ornament consisting in early stages of growth of regularly arranged, narrow concentric 
riblets, separated by broader intervals ; in later growth-stages these are replaced by 
irregular rugae. 

Holotype. No. LL. 35154, ex B.P. Coll. The only specimen. 

Locality and horizon. Magole, 5 miles N.W. of Kidugallo, Tanganyika ; 
Bajocian. 

Remarks. Its much larger size distinguishes this species from Corbula tangany- 
icensis sp. nov., which is very similar in shape. 

Corbula earnest sp. nov. 
PI. 19, figs. 19a, b, c 

Specific name. After Dr. F. E. Eames, Chief Palaeontologist of the British 
Petroleum Co., Ltd. 

Diagnosis. Of large-medium size for the genus, pyriform but not distinctly- 
rostrate posteriorly, length (16 mm.) exceeding one and a half times the height 
(which may, however, have been somewhat reduced by distortion) ; fairly strongly 



i2 4 JURASSIC BIVALVIA AND GASTROPODA 

inflated, subequivalve. Umbones broadly rounded, situated at about anterior third 
of length, and well incurved to the prosogyrous beaks. Lunular region well im- 
pressed. Antero-dorsal outline slightly concave, sloping steeply to the low, abruptly 
rounded anterior end of the shell. Ventral margin asymmetrical, moderately con- 
vex anteriorly, flattened posteriorly except at extreme end, which bends up sharply 
to the angular posterior extremity of shell. Postero-dorsal outline moderately 
convex except posteriorly, where the actual dorsal margin emerges from behind the 
umbonal profile. Posterior margin short, straight, very oblique, forming obtuse 
angle with postero-dorsal margin. Posterior umbonal ridges well defined, sigmoidal. 
Ornament consisting of rounded concentric riblets separated by much narrower 
intervals and regularly spaced in all stages of growth. 

Holotype. No. LL. 35155, ex B.P. Coll. The only specimen. 

Locality and horizon. 6 miles N.W. of Kidugallo, Tanganyika ; Bajocian. 

Remarks. In shape this species, with its gradual posterior taper, bears a very 
slight resemblance to the German Bajocian species C. involuta Munster (in Goldfuss, 
1840 : 250, pi. 151, figs. 14a, b), which needs re-describing on the basis of additional 
material. It differs from Goldfuss's type-specimen (re-illustrated by Kuhn, 1938 : 
142, pi. 5, fig. y), which is 10 mm. long, in its larger size, its more elongate outline, 
and its much stronger inflation. 

Corbula asaharbitensis sp. nov. 
PI. 19, figs. i8a, b 

Diagnosis. Rather small (length of holotype 5-5 mm.), subtrigonal, well elongated, 
height about three-fifths of length ; inflation moderate ; whether equivalve or not 
uncertain. Umbones not prominent, just posterior to mid-length, slightly opistho- 
gyrous ; an umbonal ridge present in each valve, crossing shell to ventral margin 
with slight posterior inclination. Posterior end of valves, beyond the umbonal ridge, 
compressed and subrostrate, tapering to a narrow extremity and with slightly con- 
cave dorsal margin and almost straight ventral margin. Antero-dorsal outline 
feebly convex, gently sloping ; anterior margin evenly rounded, curved in continuity 
with the ventral margin, which is strongly convex along the anterior half of its length. 
Surface of shell anterior to the umbonal ridge ornamented with evenly spaced con- 
centric ridges crossed by radial threads, forming a reticulate pattern ; posterior end 
of shell ornamented with radial riblets only, about 8 in number. The ornament is 
similar on the two valves. 

Holotype and paratypes. Holotype, no. LL. 13230 ; several paratypes. 

Locality and horizon, i mile N. of Asaharbito, N.E. Kenya ; Bathonian [? or 
Callovian], Asaharbito Beds. 

Remarks. Before the more complete specimens had been extracted from the 
matrix it was thought that this species might be related to the European Bathonian 
form Corbula hulliana Morris, but it is much more elongate than that species and also 
differs in the presence of radial ornament on both valves. It is a little like the Kim- 



FROM TANGANYIKA AND KENYA 125 

meridgian species Corbida vomer Contejean (i860 : 254, pi. 10, figs. 29, 30), but is 
very much smaller and differs considerably in the direction of its umbonal ridge. 



Corbula kailtaensis sp. nov. 
PL 19, figs. 13a, b 



Diagnosis. Of medium size for the genus (length of holotype 9-6 mm.), pyriform, 
height two-thirds of length. Left (and only known) valve gibbose, with a short, 
narrow posterior rostrum ; umbo broadly rounded, prominent, slightly anterior to 
mid-length ; antero-dorsal outline very slightly concave, sloping steeply to the 
broadly rounded anterior extremity of the shell ; ventral margin strongly convex, 
symmetrical except for a broad, ill-defined sinus at the beginning of the posterior 
rostrum ; postero-dorsal outline parasigmoidal ; no distinct umbonal ridge. Orna- 
ment consisting of narrow and slightly unevenly spaced concentric riblets. 

Holotype. No. L. 92036. The only specimen. 

Locality and horizon. Kailta, Golberobe hills, N.E. Kenya ; Oxfordian, 
Golberobe Beds. 

Remarks. This species rather closely resembles Corbula buckmani Lycett (1863 : 
63. pL 37. fig- 8), from the Bathonian of England, but in that species there is an obli- 
que posterior margin which forms an obtuse angle with the hinge-margin, and the 
narrow posterior rostrum characteristic of the present form is lacking. C. glosensis 
Zittel & Goubert (figured Chavan 1952, pi. 4, figs. 76-79), from the Upper Oxfordian 
of Cordebugle, Calvados, France, is not so distinctly rostrate. 

Superfamily PHOLADOMYACEA 

Family PHOLADOMYIDAE Gray 1847 

Genus PHOLADOMYA G. B. Sowerby 1823 

Pholadomya reticulata Agassiz 
PL 20, fig. 2 

1842. Pholadomya reticulata Agassiz : 80, pi. 4, figs. 4-6 ; pi. 4c, figs. 1-4. 

1874. Pholadomya reticulata Ag. ; Moesch : 28, pi. 9, figs. 2, 4, 5, 9-11. 

1893. Pholadomya reticulata Ag. ; Choffat : 11, pi. 4, figs. 4-7. 

1929. Pholadomya reticulata Ag. ; Lanquine : 203, pi. 7, fig. 8. 

Material. Three specimens (nos. LL. 35076-78). 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. The largest specimen, the original length of which was slightly more 
than 25 mm., is much eroded, but the smaller specimen illustrated is ornamented with 
rather coarse concentric folds crossed by narrow radial riblets which are present on 
all parts of the shell. There is close agreement with the illustrations cited above. 
This relatively small Pholadomya was originally described from beds of Upper Liassic 
age. Its range extends, according to Moesch, into the Bajocian. 



lib JURASSIC BIVALVIA AND GASTROPODA 

Pholadomya lirata (J. Sowerby) 

PI. 20, fig. 8 

[8180. Cardita? lirata J. Sowerby : 220, pi. 197, fig. 3. 

1910. Pholadomya cavinata Goldfuss ; Dacque : 31, pi. 5, fig. 7. 

1916. Pholadomya cavinata Goldfuss ; Douville : 55, pi. 6, fig. 8. 

1935a. Pholadomya lirata (J. Sowerby) ; Cox : 190, pi. 21, figs. 8, 9. 

1939. Pholadomya carinata Goldfuss ; Stefanini : 259, pi. 27, fig. 2. 

1948. Pholadomya lirata (J. Sowerby) ; Cox & Arkell : 43. 

i960. PlioladoDiva lyrata J. de C. Sowerby ; Joubert, pi. 11, fig. 6. 

Material. Several specimens. 

Localities and horizons. Kidugallo Station and \\ miles to the east, Central 
Railway, Tanganyika ; Bajocian, Station Beds. 2 miles E. of Magindu Station, 
Central Railway, Tanganyika ; Callovian. 3 miles W. of Melka Biini, N.E. Kenya ; 
Callovian, Rukesa Shales. 

Remarks. This widespread species was discussed by me in 1935. The earlier 
authors who recorded it from East Africa cited it under the name P. carinata Gold- 
fuss. 

Pholadomya ovalis (J. Sowerby) 
PI. 20, fig. 1 

1819a. Lutraria ovalis J. Sowerby : 47, pi. 226, fig. 1 only. 

1842. Pholadomya oindum Agassiz : 119, pi. 3, figs. 7-9 ; pi. 3ft, figs. 1-6. 

1874. Pholadomya ovulum Agassiz ; Moesch : 48, pi. 20, figs. 1-11. 

1910. Pholadomya angustata (Sow.) ; Dacque : 32, pi. 5, fig. 8 (non Sowerby sp.). 

1929. Pholadomya protei (Brongniart) ; Weir : 33, pi. 3, fig. 10 {non Brongniart sp.). 

1948. Pholadomya ovalis (J. Sowerby) ; Cox & Arkell : 44. 

i960. Pholadomva ovalis (J. Sowerby) ; Joubert, pi. 11, figs. 8a, b. 

Material. Two specimens (nos. L. 98277, L. 92075). 

Localities and horizons. Hagardulun, 25 miles N.E. of Tarbaj, N.E. Kenya ; 
Bathonian-Callovian, Bur Mayo Limestones. Kulong, 2 miles S.W. of Muddo Erri, 
N.E. Kenya ; Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Pholadomya protei (Brongniart) 
1821. Cardium protei Brongniart : 554, pi. 7, figs. 7a-c. 



1872. Pholadomya protei (Brongniart) 

1875. Pholadomya protei (Brongniart) 

1935a Pholadomya protei (Brongniart) 

1939. Pholadomya protei (Brongniart) 



de Loriol : 169, pi. 10, figs. 13-15. 

Moesch : 79, pi. 30, figs. 1, 2. 

Arkell : 333, pi. 46, figs. 8, 9 ; pi. 47, figs. 1-4. 

Stefanini : 263, pi. 27, figs. 6-8. 



Material. One specimen (no. LL.11807). 

Locality and horizon. Just W. of Mabokweni, 4 miles N.W. of Tanga, Tan- 
ganyika ; Kimmeridgian. 

Remarks. This species, which has been misidentified by some authors, is 
characterized by its relatively short outline and by its small number (3-6) of costae, 



FROM TANGANYIKA AND KENYA 127 

which are closely arranged on the middle of the shell, the most anterior one standing 
out as a sharp keel. Although its posterior end is broken away, the specimen now 
recorded seems to be a very typical example of the species. The specimens from 
Somaliland figured as P. protei by Dacque (1905 : 140, pi. 15, figs. 1-3) and one from 
Rukesa, N. Kenya, considered by Weir (1929 : 33, pi. 3, fig. 10) to be a young indi- 
vidual of the species, were wrongly identified. 



Pholadomya hemicardia Roemer 
PI. 20, fig. 5 

1836. Pholadomya hemicardia Roemer : 131, pi. 9, fig. 18. 

1874. Pholadomya hemicardia Roemer ; Moesch : 58, pi. 23, figs. 1-6 ; pi. 24, fig. 11. 

1935a. Pholadomya hemicardia Roemer ; Arkell : 336, pi. 46, figs. 5-7. 

i960. Pholadomya hemicardia Roemer ; Joubert, pi. 11, figs. 5a, b. 

Material. Two specimens (nos. L. 92186, LL. 35156). 

Localities and horizons. Mandawa-Lonji creek traverse, Mandawa area, Tan- 
ganyika ; Upper Oxfordian. Hegalu hills, 2 miles N. of Finno, N.E. Kenya ; 
Upper Kimmeridgian, Dakacha Limestones. 

Remarks. The more complete specimen is 33 mm. long, with the posterior end 
of the shell rather angular and situated above mid-height. The ornament consists 
of weak, irregular concentric undulations crossed by weak radial riblets, which are 
scarcely perceptible on the posterior part of the surface. The specimens appear to 
fall within the range of variation of P. hemicardia, which in Europe occurs in the 
Oxfordian and Kimmeridgian. 



Genus HOMOMYA Agassiz 1843 
Homomya inornata (J. de C. Sowerby) 

18406. Pholadomya? inornata J. de C. Sowerby : 327, pi. 21, fig. 8. 

1874. Pholadomya inornata Sowerby ; Moesch : 53. 

1907a. Pholadomya inornata Sowerby ; Cossmann : 134, pi. 1, fig. 17. 

1912. Pholadomya inornata Sowerby ; Lissajous : 92, pi. 11, fig. 21. 

1921. Pholadomya inornata Sowerby ; de la Bouillerie : 35, pi. 4, fig. 10. 

1924. Pholadomya (Flabellomya) ovulum Agassiz ; Cossmann : 53, pi. 7, figs. 3- 

Material. One specimen (no. L. 92154). 

Locality and horizon. 3! miles W. of Melka Biini, N.E. Kenya. Callovian, 
Rukesa Shales. 

Remarks. This species, which is ornamented with concentric ribs undulating 
slightly in places and may also bear a few faint radial threads (actually just visible 
on Sowerby 's holotype), was described originally from the Callovian of India. It 
has been recorded by authors cited above from the Callovian of France. Cossmann 
(1924), however, has suggested that the French specimens would be more correctly 
identified as Pholadomya ovulum Agassiz (= P. ovalis (J. Sowerby)). This view is 



128 JURASSIC BIVALVIA AND GASTROPODA 

not here accepted. Although radial ornament is relatively weak and variable in 
P. ovalis, it is more distinct than in any specimens which have been recorded as P. 
inornata, a species which it seems preferable to include in Homomya. The African 
fossil now recorded is imperfect, but agrees well with typical specimens from India. 



Homomya rahmuensis sp. nov. 
PL 20, figs. 3a, b 

i960. Homomya sp. nov. ; Joubert, pi. 11, figs, ga, h. 

Diagnosis. Small for the genus (length of holotype 43 mm.), oblong-ovate, 
height about three-fifths of length ; inflation moderate (22 mm. in holotype) and 
even, greatest at about mid-length ; posterior gape narrow. Umbones rather 
narrow, protruding only slightly, placed at about the anterior fifth of the length ; 
posterior umbonal ridge, bordering a rather broad but shallow escutcheon, ill-defined 
except near the umbones. Postero-dorsal and ventral margins straight, elongate, 
sub-parallel. Posterior margin of feeble convexity, sub-vertical in its general direc- 
tion. Ornament consisting of weak, irregular concentric folds. 

Holotype. No. L. 92260. The only specimen. 

Locality and horizon. Uacha, 6 miles S. of Rahmu, N.E. Kenya. Oxfordian, 
Rahmu Shales. 

Remarks. This species is comparable to H. censoriensis (Cotteau) (Peron, 1906 : 
43, pi. 1, fig. 1), Oxfordian of France, but is not so high at its posterior end. H. 
corallina de Loriol (1894a : 80, pi. 6, figs. 1, la), Lower Kimmeridgian of France, is 
more gibbose and slightly less elongate. 



Homomya hortulana Agassiz 
PL 20, fig. 4 

1843. Homomya hortulana Agassiz : 155, pi. 15. 

1872. Pholadomya hortulana (Agassiz); de Loriol : 166, pi. 10, fig. 16. 

1893. Pholadomya (Homomya) hortulana (Agassiz) ; Choffat : 33, pi. 9, figs. 2-6. 

1933. Homomya cf. hortulana Agassiz ; Dietrich : 55, pi. 7, fig. 104. 

Material. Three specimens. 

Localities and horizons. N. of Kipande, Tendaguru, Tanganyika ; Upper 
Kimmeridgian, Nerinella Bed. Mtapaia road, Tendaguru ; Upper Kimmeridgian, 
" Trigonia smeei " Bed. 

Remarks. The prominence of the umbones varies considerably in European speci- 
mens of this species. They are very broad and depressed in the East African speci- 
mens now recorded, but these can be matched with published figures of specimens 
from Europe, and it seems unnecessary to follow Dietrich in qualifying their specific 
identification. 



FROM TANGANYIKA AND KENYA 129 

Genus GONIOMYA Agassiz 1841 

Goniomya trapezicostata (Pusch) 
PI. 21, figs. 2, 3 

1836. Lutraria trapezicostata Pusch : 80, pi. 8, figs. loa-c. 

1840. Lysianassa ornata Munster ; Goldfuss : 264, pi. 154, fig. 12. 

1842. Goniomya inflata Agassiz : 20, pi. 1, fig. 15. 

1852. Pholadomya trapezina Buvignier : 8, pi. 8, figs. 14-18. 

1900. Goniomya cf. trapezina (Buvignier) ; Miiller : 536, pi. 18, figs. 2, 2a. 

1924. Goniomya trapezicostata (Pusch) ; Cossmann : 51, pi. 7, figs, g, 10. 

Material. Two specimens (nos. L. 54080, LL.35I57), the second ex B.P. Coll. 

Localities and horizons. i£ miles E. of Kidugallo Station, Central Railway, 
Tanganyika. Bajocian. £ mile N.W. of bridge over Mkulumuzi river, 2 miles W. of 
Tanga, Tanganyika ; Callovian. 

Remarks. In this species the steep oblique ribs on the anterior and posterior 
parts of the surface are separated in all stages of growth by a horizontal rib, instead 
of meeting to form a series of V's, as in most species of the genus. In the specimen of 
Bajocian age now recorded the intervening horizontal ribs are shorter than in the 
Callovian specimen, which agrees better with the typical G. trapezicostata. The 
difference, however, does not seem important enough to justify its specific separation. 
In Europe G. trapezicostata occurs in the Callovian and Oxfordian. 

Goniomya literata (J. Sowerby) 

1819a. Mya? literata J. Sowerby : 45, pi. 224, fig. 1. 

1819a. Mya v. scripta J. Sowerby : 46, pi. 224, figs. 2-5. 

1935a. Goniomya literata (Sowerby) ; Arkell : 344, pi. 48, figs. 1-7. 

1939. Goniomya literata (Sowerby) ; Stefanini : 254, pi. 26, figs. 3a, b. 

Material. One specimen (no. LL. 16846). 

Locality and horizon. Scarp face, eastern margin of Makoko plain, Bagamoyo 
hinterland, Tanganyika ; Oxfordian. 

Remarks. In this specimen the convergent oblique ribs almost die out at mid- 
growth, particularly on the posterior part of the surface. In this respect the speci- 
men agrees with G. marginata Agassiz, as interpreted by de Loriol (1872 : 187, pi. 12, 
figs. 3, 4) and Boden (191 1 : 58, pi. 6, figs. 2, 2a), although it is to be noted that 
Agassiz's (1842, pi. 1, figs. 12-14 ; pi. ic, fig. 15) original figures of G. marginata do 
not show this fading away of the ribs. Arkell (1935a : 346) was of the opinion that 
G. marginata, even as interpreted by the authors cited, is inseparable from G. literata. 

Genus OSTEOMYA Moesch, 1874 
Osteomya dilata (Phillips) 

1829. Mya dilata Phillips : 155, pi. 11, fig. 4. 

1855. Myacites dilatus (Phillips) ; Morris & Lycett : 114, pi. 10, figs. 5a, b. 



130 JURASSIC BIVALVIA AND GASTROPODA 

1923. Goniomeris dilatata (Phillips ); Lissajous : 195, pi. 32, figs. 2-5. 
1948. Osteomya dilata (Phillips) ; Cox & Arkell : 45. 

Material. Two specimens (nos. LL.i 1566-7). 

Locality and horizon. Kidugallo Station, Central Railway, Tanganyika. 
Bajocian, Station Beds. 

Remarks. Although distorted, the specimens now recorded are unmistakable 
examples of this species. Its range in Europe is from Bajocian to Callovian. It 
has been recorded from the Bajocian of Madagascar, but not from East Africa pre- 
viously. 



Family MYOPHOLADIDAE Cox 1964 

Genus MYOPHOLAS Douville 1907 

Myopholas manderaensis sp. nov. 
PI. 19, fig. 20 

i960. Myopholas sp. nov. : Joubert, pi. 11, fig. 10. 

Diagnosis. Rather small for the genus, elongate-ovate, with the length (31 mm. 
in the holotype) about z\ times the height (12 mm.). Inflation only moderate, but 
possibly diminished in the course of fossilization. Umbo very broadly rounded, 
placed at about the anterior third of the length, and not protruding above the postero- 
dorsal margin, which slopes gradually towards the narrowly rounded posterior extre- 
mity. Ventral margin with a broad and very shallow median sulcus. Ornament of 
anterior two-thirds of surface consisting of 23 narrow radial ribs, the most anterior 
three of which are separated by relatively broad intervals and the remainder by much 
narrower ones. The most posterior of these ribs stands out slightly more prominent- 
ly than the others ; the posterior third of the surface, lying beyond it, bears a few 
ribs which are just visible in the earlier growth-stages and then fade away partly or 
completely, leaving the surface almost smooth. 

Holotype. No. L. 92271, the external mould of a right valve. There are also 
two very imperfect specimens. 

Locality and horizon. Matasafara, 15 miles W. of Mandera, N.E. Kenya ; 
uppermost Jurassic, Gudediye Beds. 

Remarks. The virtual absence of ribbing on the posterior third of the surface 
distinguishes this species from the European Upper Jurassic forms Myopholas mul- 
ticostata (Agassiz) and M. percostata Douville (Douville, 1907b, pi. 2, figs. 6, 7 and 
figs. 4, 5 respectively) and is more suggestive of the Neocomian shell M. semicostata 
(Agassiz) (Douville, 19076, pi. 2, fig. 8), which, however, has fewer costae on the 
anterior part of its surface. 



FROM TANGANYIKA AND KENYA 131 

Family PLEUROMYIDAE Dall 1900 
Genus PLEUROMYA Agassiz 1845 

Pleuromya didimtuensis sp. now 

PL 19, fig. 16 

Diagnosis. Of small-medium size (length of largest specimen c. 24 mm.), sub- 
ovate, somewhat projecting postero-dorsally and with subrostrate anterior end ; 
inequilateral, height about two-thirds of length, beaks at anterior third of length ; 
shell well inflated mesially, but somewhat compressed postero-dorsally. Umbones 
broadly rounded, well incurved to the beaks, which are moderately prosogyrous. 
Postero-dorsal margin feebly convex, subhorizontal, forming a slightly acute angle 
with the backward-sloping posterior margin ; ventral margin strongly convex 
posteriorly, where it joins the posterior margin, flattened and slightly convergent 
with the postero-dorsal outline anteriorly ; antero-dorsal outline feebly concave, 
steeply sloping ; anterior margin low, strongly convex. Ornament consisting of 
narrow, rounded concentric ribs, a little sinuous and irregular in places. Internal 
characters not observable. 

Holotype and paratypes. Nos. LL.35079 and LL.35080-81 respectively, three 
specimens in all. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. Owing to erosion the specimens do not clearly show the projecting 
postero-dorsal corner of the shell, which is one of its most distinctive characters, but 
this can be restored by studying the growth-lines. In this feature the present species 
resembles Pteromya tatei (Richardson & Tutcher) (1916 : 52, pi. 8, figs, ^a-c), from 
the basal Hettangian of England, but that species is larger and has a more strongly 
convex ventral margin. 



Pleuromya uniformis (J. Sowerby) 
PL 20, fig. 6 

1813a. Unto uniformis J. Sowerby : 83, pi. 33, fig. 4. 

1900. Pleuromya tellina Agassiz ; Miiller : 536, pi. 18, figs. 3-5. 

1914&. Pleuromya tellina Agassiz ; Hennig : 168, pi. 14, fig. 5. 

1935a. Pleuromya uniformis (J. Sowerby) ; Arkell : 325, pi. 45, figs. 1-13. 

1948. Pleuromya uniformis (J. Sowerby) ; Cox & Arkell : 40. 

Material. Several specimens. 

Localities and horizons. Scarp face, eastern margin of Makoko plain, Baga- 
moyo hinterland, Tanganyika ; Oxfordian. Kinjele, 5 miles W. of Mtapaia, N. of 
Tendaguru, Tanganyika ; Upper Kimmeridgian, Indogrammatodon bed. 



132 JURASSIC BIVALVIA AND GASTROPODA 

Pleuromya calceiformis (Phillips) 
PI. 20, fig. 9 

1829. Mya calceiformis Phillips : 155, pi. 11, fig. 3. 

1863. Myacites calceiformis (Phil.); Lycett : 80, pi. 42, figs. 1, 1a. 

1934a. Pleuromya calceiformis (Phil.) ; Arkell : 324, pi. 44, figs. 12, 12a. 

Material. One specimen (no. LL.35158), ex B.P. Coll. 

Locality and horizon. Mandawa-Lonji creek traverse, Mandawa area, Tangan- 
yika ; Upper Oxfordian. 

Remarks. The specimen now recorded is in every way typical of the species. 
This has not been recorded previously from East Africa or from anywhere in the 
Indian Ocean region. 

Family CERATOMYIDAE Arkell 1934 
Genus CERATOMYA Sandberger 1864 

Ceratomya tanganyicensis sp. no v. 

PI. 21, figs. la, b, c 

Diagnosis. Of medium size (length 41 mm.), ovate with a trigonal tendency, 
moderately inequilateral, height four-fifths of length, beaks at about anterior third 
of length ; shell well inflated mesially, somewhat compressed posteriorly. Umbones 
very broadly rounded, not prominent, well incurved to the beak, which was apparent- 
ly not strongly prosogyrous for the genus, but is obscured in the only available speci- 
men. Postero-dorsal outline very feebly convex, rather steeply sloping, joining the 
fairly sharply rounded posterior margin in an even curve ; ventral margin very 
strongly convex anteriorly, almost angular posteriorly, where it bends up to the 
narrowly rounded anterior end of the shell ; antero-dorsal outline very feebly con- 
cave. Ornament of numerous narrow, rounded, subequal concentric ribs, which 
number rather more than 20 to the cm. 

Holotype. No. LL.35159. The only specimen. 

Locality and horizon. Lihimaliao creek, at a point near Mbaru creek, Man- 
dawa area, Tanganyika ; Bajocian (?), Pindiro Shales. 

Remarks. The closeness of the concentric ribbing distinguishes this from all other 
post-Liassic species of the genus. In C. madagascariensis (Thevenin) (19086 : 28, 
pi. 3, figs. 9, 9a), from the Upper Lias of Madagascar, the shell is higher and less 
elongated. 

Ceratomya concentrica (J. de C. Sowerby) 
PI. 20, fig. 7 

1825a. Isocardia concentrica J. de C. Sowerby : 147, pi. 491, fig. 1. 

1855. Isocardia concentrica Sowerby ; Morris & Lycett : 108, pi. 10, figs. 3a, b (non pi. 15, 
figs. ia, b). 



FROM TANGANYIKA AND KENYA 133 

1863. Ceromya concentrica (Sowerby) ; Lycett, pi. 36, fig. 5. 
1948. Ceratomya concentrica (Sowerby) ; Cox & Arkell : 41. 
i960. Ceratomya concentrica (Sowerby) ; Joubert, pi. 10, figs, ga, b. 

Material. About four specimens. 

Localities and horizons. 3! miles W. of Melka Biini, N.E. Kenya ; Callovian, 
Rukesa Shales. Kulong, 2 miles S.W. of Muddo Erri, N.E. Kenya ; Callovian [?- 
Lower Oxfordian], Muddo Erri Limestones. 

Remarks. In the specimens on which the ornament is best preserved the con- 
centric ribs are numerous and closely arranged, as in specimens from the Great Oolite 
of England. There is also an imperfect specimen from the Bajocian of Kidugallo, 
Tanganyika, which seems to be very similar to C. concentrica but is more coarsely 
ribbed. This may perhaps belong to the related species C. bajociana (d'Orbigny). 

Ceratomya pittieri (de Loriol) 
PI. 21, fig. 4 

1883. Ceromya pittieri de Loriol : 25, pi. 6, figs. 3, 4. 

1910. Ceromya concentrica (Sow.) ; Dacque : 33, pi. 5, fig. 6 only (non Sowerby sp.). 

Material. One specimen (no. LL. 35160), ex B.P. Coll. 

Locality and horizon. Magindu, Central Railway, Tanganyika ; Callovian. 

Remarks. This specimen, which is 94 mm. long, is a well elongated Ceratomya 
with an almost terminal, only slightly protruding umbo which is strongly incoiled to 
the beak. A slight radial depression of the flank appears at mid-growth and termin- 
ates at the ventral margin near its anterior end. The ventral margin diverges 
gradually from the hinge-margin in a posterior direction. The surface ribs, although 
partly obliterated by erosion in places, can be seen to be regularly concentric and 
fairly closely arranged. 

Except for the presence of the radial depression, the shape of the shell agrees with 
de Loriol's figures of C. pittieri, the type specimens of which came from the Callovian 
Mytilus Beds of the Alps of Vaud, Switzerland. The Abyssinian Kimmeridgian (?) 
species C. paucilirata (Blanford), especially as figured by Futterer (1897, pi. 22, 
fig. 1) also resembles the present specimen in shape, but its concentric ribs are not so 
closely arranged. These forms are very close to de Loriol's (1872, pi. 12, fig. 13) 
" var. cylindrica " of C. excentrica, an Upper Oxfordian-Kimmeridgian species highly 
variable in form and ornament. In view of the Callovian age of the specimen now 
recorded, however, it seems most satisfactory to identify it as C. pittieri. 

Ceratomya wimmisensis (Gillieron) 

1883. Ceromya concentrica (Sowerby) ; de Loriol : 18, pi. 5, figs. 1-5 {non J. de C. Sowerby 

sp.). 
1886. Ceromya wimmisensis Gillieron : 141. 

1918. Ceromya wimmisensis Gillieron ; Gerber : 12, pi. 1, figs. 3-6. 
1929. Ceratomya wimmisensis (Gillieron) ; Weir : 31, pi. 3, fig. 2. 



134 JURASSIC BIVALVIA AND GASTROPODA 

1929. PCeratomya cf. wimmisensis (Gillieron) ; Weir : 31, pi. 3, fig. 1. 
1935a. Ceratomya wimmisensis (Gillieron) ; Cox : 186, pi. 20, figs. 6a, b. 
IQ 39- Ceratomya wimmisensis (Gillieron) ; Stefanini : 248, pi. 25, figs. 5, 6. 

Material. One specimen (no. L.83881). 

Locality and horizon. 14 miles W.S.W. of Rahmu, N.E. Kenya. Callovian 
[?-Lo\ver Oxfordian], Muddo Erri Limestones. 

Remarks. This specimen shows the abrupt discordancies in ribbing characteristic 
of this species, patches of oblique ribs occupying parts of the surface and concentric 
ribs the remainder. The arrangement of the ribbing is altogether dissimilar on the 
two valves. The specimen is not well enough preserved for illustration. 



Ceratomya wilder riensis sp. no v. 

PI. 21, fig. 5 

i960. Ceratomya excentrica (Roemer) ; Joubert, pi. 11, fig. 1 (non Roemer sp.). 

Diagnosis. Shell moderately large (length of holotype c. 87 mm.), ovate, with 
height about three-quarters of length, strongly inequilateral, evenly and moderately 
strongly inflated. Umbo terminal, strongly prosogyrous and incurved, its outline 
continuous with postero-dorsal outline of shell, which rises slightly above it before 
curving gently down to meet the evenly convex posterior margin. Ventral margin 
moderately and evenly convex. Umbonal ridges absent. Ornament consisting of 
closely and fairly evenly arranged, rounded concentric ribs (about 8 to the cm. on 
middle of shell), separated by narrower intervals. 

Holotype and paratype. Nos. L. 92226 and L. 92246 respectively, two speci- 
mens in all. 

Localities and horizon. Dusse, i\ miles S.E. of Rahmu, N. Kenya (type- 
locality). Wilderri hill, 11 miles S.S.W. of Rahmu. Both Upper Oxfordian, Seir 
Limestones. 

Remarks. This species, with its purely concentric ornament, belongs to the group 
of Ceratomya concentrica (J. de C. Sowerby), differing from that species in the termin- 
al position of its umbo, in the even convexity of its surface (the postero-dorsal region 
is not in the least pinched-in), and in its larger size. In C. paucilirata (Blanford) 
(1870 : 203, pi. 8, fig. 6 ; also Futterer 1897 : 610, pi. 22, fig. 1), Upper Jurassic of 
S. Abyssinia, the umbo is more prominent and less anteriorly placed, the postero- 
dorsal region is not so evenly convex, and the concentric ribs are broader. In C. 
egerkingensis (Gerber) (1918 : 6, pi. 1, fig. 1), Lower Kimmeridgian of Switzerland, 
the umbo is much more prominent and less anteriorly placed. 



FROM TANGANYIKA AND KENYA 135 

Ceratomya excentrica (Roemer) 
PI. 20, fig. 10 

1836. Isocardia excentrica Voltz MS. ; Roemer : 106, pi. 7, figs. ^a-c. 

1842. Ceromya excentrica (Voltz) ; Agassiz : 28, pis. 8a-c. 

1897. Ceromya excentrica (Voltz) ; Agassiz ; Futterer : 608, pi. 22, figs. 2, ia. 

1929. Ceratomya excentrica (Weir) (sic) ; Weir : 31, pi. 3, fig. 4. 

1934a. Ceratomya excentrica (Roemer) ; Arkell : 316, pi. 43, figs, u, 12. 

J 939- Ceratomya excentrica (Voltz) ; Stefanini : 249, pi. 25, fig. 7. 

i960. Ceratomya excentrica (Roemer) ; Joubert, pi. 10, figs. 10a, b (non pi. 11, fig. 1). 

Material. Several specimens. 

Localities and horizons. Hereri river crossing, 3 miles S. of Melka Kunha, 
N.E. Kenya ; Kimmeridgian, Hereri Shales. 1 mile S.S.W. of Melka Dakacha, 
N.E. Kenya ; Upper Kimmeridgian, Dakacha Limestones. 

Remarks. The specimens now recorded are typical in every way, showing coarse 
ribs with various degrees of obliquity. 

Superfamily PANDORACEA 

Family THRACIIDAE Stoliczka 1870 

Genus THRACIA Leach 1823 

Thracia lens (Agassiz) 

PL 21, fig. 8 

1845. Corimya lens Agassiz : 267, pi. 36, figs. 1-15. 

1912. Corymya lens Ag. ; Lissajous : 103, pi. 12, fig. 21. 

1926. Thracia aff. lenii Ag. ; Schmidtill : 82, pi. 11, figs. 20a, b. 

Material. One specimen (no. LL.35161), ex B.P. Coll. 

Locality and horizon. Lihimaliao creek, at a point near Mbaru creek, Mandawa 
area, Tanganyika ; Bajocian (?), Pindiro Shales. 

Remarks. This specimen, which is about 28 mm. long, agrees well with the 
original figures of the species in its elliptical outline, its broadly rounded, depressed 
umbo lying well posterior to mid-length, its evenly convex, gently sloping postero- 
dorsal outline, and its evenly concave, gently sloping antero-dorsal outline. The 
right valve is crushed. This species was originally described from the Bajocian of 
Switzerland and has been recorded from the Bathonian of France, Germany, and 
Sardinia. 

Thracia viceliacensis d'Orbigny 
PI. 21, fig. 9 



1850a. Thracia viceliacensis d'Orbigny : 306. 
1906. Thracia viceliacensis d'Orb 
1911a. Thracia viceliacensis d'Orb 
191 1. Thracia viceliacensis d'Orb 



Cossmann : 288, pi. 2, figs. 14—19. 
Thevenin : 134, text-fig. 
Flamand : 903, pi. 11, figs. 17a, b. 



136 



JURASSIC BIVALVIA AND GASTROPODA 



19 1 2. Thracia viceliacensis d'Orb. 

1916. Thracia viceliacensis d'Orb. 

1925. Thracia viceliacensis d'Orb. 

1935a. Thracia viceliacensis d'Orb. 

*939- Thracia viceliacensis d'Orb. 



Lissajous : 102, pi. 12, fig. 20. 
Douville : 56, pi. 6, fig. 9. 
de la Bouillerie : 89, pi. 9, fig. 4. 
Cox : 190, pi. 20, fig. 5. 
Stefanini : 266, pi. 27, figs. 9, 10. 



Material. One specimen (no. LL.35162), ex B.P. Coll. 

Locality and horizon. Lonji creek, W. of Mandawa, Tanganyika ; Callovian. 

Remarks. This specimen, which is 36 mm. long, is in every way typical of T. 
viceliacensis, a species characterized by its prominent, obtusely angular, submedian 
umbones and not very elongated form. The species was originally described from the 
Bathonian of France and has been recorded from beds attributed to that stage in 
Algeria and Sinai as well as in Europe. In British Somaliland, however, it has been 
found in beds regarded as Callovian. A specimen from beds of doubtful but possibly 
post-Callovian age at Dakatch, Italian Somaliland, attributed by Weir (1929 : 34, 
pi. 3, fig. 19) to T. viceliacensis is not so tall and trigonal as typical specimens of the 
species and may belong to a distinct form. 



Superfamily POROMYACEA 

Family CUSPID ARIIDAE Dall 1886 

Genus CUSPID ARIA Nardo 1840 

Cuspidaria ayersi sp. no v. 

PL 21, figs. 6a, b, ya, b 

Specific name. After Mr. F. M. Ayers, of the Geological Survey of Kenya. 

Diagnosis. Shell of small-medium size (length of holotype 10-3 mm.), slightly 
longer than high, subalate posteriorly. Left (and only known) valve strongly in- 
flated, with very prominent and narrowly rounded umbo situated just anterior to 
mid-length and strongly incurved to the prosogyrous beak. Anterior margin 
strongly convex, curved in continuity with ventral margin, the anterior part of which 
has a shallow sinus in some specimens. Posterior wing of feeble convexity, rounded 
at its tip, which is level with or extends to a variable extent beyond the posterior 
extremity of the ventral margin ; wing separated from inflated body of valve by 
radial sulcus to which there corresponds a sinus of posterior margin. Ornament 
consisting of regularly arranged concentric ribs absent from posterior wing in some 
specimens. 

Holotype and paratypes. Holotype, no. LL. 13246. About 15 paratypes. 

Locality and horizon, i mile N. of Asaharbito, N.E. Kenya ; Bathonian [? or 
Callovian], Asaharbito Beds. 

Remarks. In this species the ventral margin extends further in a posterior 
direction than in the European Kimmeridgian species Cuspidaria fontannesii (de 



FROM TANGANYIKA AND KENYA 137 

Loriol) (1878 : 141, pi. 22, figs. 2, 3) or in the two Tithonian species C. picteti (Zittel) 
(1870 : 118, pi. 12, fig. 7) and C. transylvanica (Neumayr) (1873 : 205, pi. 43, fig. 5) ; 
in consequence, the posterior margin has a well-defined sinus. These are the two 
most closely comparable species described previously. 



Class GASTROPODA Cuvier 

Subclass PROSOBRANCHIA Milne Edwards 

Superfamily EUOMPHALACEA 

Family EUOMPHALIDAE de Koninck 1881 

Genus DISCOHELIX Dunker 1848 

Discohelix didimtuensis sp. nov. 
PI. 22, figs. la, b, c, d 

Diagnosis. Rather small (diameter of largest specimen 10-5 mm.), discoidal, 
compressed, upper face flat, lower face umbilicate. Outer face low, slightly concave, 
inclined inwards to a slight extent in an abapical direction, and separated from upper 
face and from base by tuberculate carinae which project in an abaxial direction. 
Some tubercles of both carinae are elongated transversely, so that on both the upper 
face and the base they remain partly visible along the outer suture on the earlier 
whorls, and in some specimens they are continued across the upper face of these 
whorls by weak transverse riblets. The entire surface of the shell is ornamented with 
delicate spiral threads. 

Holotype AND paratypes. Nos. GG.10246 and GG. 10247-49 respectively, four 
specimens in all. 

Locality and horizon. Didimtu hill, two miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. In Discohelix dunkeri Moore (1867 : 85, pi. 5, figs. 28, 29 ; also 
Dumortier 1874 : 141, pi. 35, figs. 18, 19), from the Upper Lias of southern England 
and France, the ornament of the shell is closely comparable to that of the new species, 
but the two carinae are less prominent and, between them, the outer face of the shell 
is feebly convex ; transverse riblets originating at the tubercles are well marked on 
both the upper face and the base. D. sinistra (d'Orbigny) (1853 : 310, pi. 322, figs. 
1-7), from the Middle Lias of France, differs in much the same manner. D. albinati- 
ensis Dumortier (1874 : 284, pi. 59, figs. 3-5 ; also Kuhn 1935 : 132, pi. 10, fig. 5), 
from the Upper Lias of France and Germany, much resembles the new species, but 
the lower of its two carinae projects abapically instead of outward, and the outer face 
of the shell is convex rather than concave. 



[38 JURASSIC BIVALVIA AND GASTROPODA 

Genus NUMMOCALCAR Cossmann 1896 

Nummocalcar mitoleensis sp. now 

PI. 22. figs. 2a, b, c 

Diagnosis. Of medium size (diameter 24 mm.), discoidal, with a barely pro- 
truding spire, the apex of which is just visible when the shell is viewed from the side, 
and with the periphery formed by a smooth, projecting carina at about mid-height. 
Outer face, above the carina, flat and inclined inwards steeply as far as an angulation 
which bears well separated, rounded nodes and forms the border of the flat upper face. 
Base, consisting of all the surface below the carina, slightly concave in profile owing 
to the presence of a broad swelling, bearing weak, transversely elongated tubercles, 
on the outer side of a smooth spiral cord which forms the margin of the moderately 
broad umbilicus. Where not eroded, the base bears weak spiral cords, but any spiral 
ornament that may have been present above the peripheral carina has been oblitera- 
ted by erosion. Aperture broader than high, but with its margin not preserved in- 
tact ; growth-lines visible below the peripheral carina show that the outer lip was 
strongly prosocline, and had a very broad sinus. 

Holotype. No. GG. 10282, ex B.P. Coll. The only specimen. 

Locality and horizon. Mpilepile stream bed, 1650 yards N.E. of Mitole road 
junction, northern Mandawa area, Tanganyika ; Upper Kimmeridgian. 

Remarks. This species belongs to a group of Jurassic and Cretaceous forms 
characterized by a carinate periphery and by tuberculate ornament on both the 
upper face of the whorls and the base, the tubercles being elongated transversely in 
some species to form ribs. The Albian species " Solarium " subornatum d'Orbigny 
(S. ornatum J. de. C Sowerby, non Lea) is a characteristic representative of this group 
and is clearly congeneric with the form now described. Until a revision of all 
Mesozoic discoidal and subdiscoidal shells can be carried out, Cossmann is followed 
in referring the species of this group to Nummocalcar. In the type species of this 
genus, however, strong transverse ribs on the upper face of the whorls end in promin- 
ent spines on the peripheral carina. It is uncertain if this genus should be included 
in the Euomphalidae, where it was placed by Cossmann, or if it should be assigned 
to the Architectonicidae or possibly to a new family. 

Superfamily PLEUROTOMARIACEA 

Family PLEUROTOMARIIDAE Swainson 1840 

Genus BATHROTOMARIA Cox 1956 

Bathrotomaria aitkeni sp. nov. 
PL 22, fig. 6 ; PI. 23, figs. la, b 

Specific name. After Dr. W. G. Aitken, lately Director of the Geological 
Survey of Nyasaland, collector of the type specimens. 

Diagnosis. Large (original height of largest specimen no mm.), trochiform, 



FROM TANGANYIKA AND KENYA 139 

with diameter approximately equal to or slightly less than height and with narrow, 
deep umbilicus. Whorls with slightly concave outer face, which is steeply and some- 
what variably inclined, and a broad ramp, varying from feebly concave to feebly con- 
vex, which forms an angle averaging about 45 ° with shell axis. Whorl shoulder 
formed by rounded spiral cord bearing selenizone. Base feebly convex, its periphery 
formed by second rounded cord which is almost of the same strength as the first and 
is just exposed in places on the spire whorls. Ornament of ramp, whorl outer face 
and base consisting of numerous spiral cords and threads of unequal strength. 
(Collabral threads, if originally present, have been obliterated by erosion in the 
specimens examined.) 

Holotype and paratypes. Nos. GG.10306 and GG.10307-08 respectively, three 
specimens in all. 

Localities and horizon. At three points along the Mandawa-Namakongoro 
stream, Mandawa-Mahokondo area, Tanganyika ; Middle-Upper Kimmeridgian. 

Remarks. Its large size distinguishes this species from any Jurassic Bathroto- 
maria described previously. The English Upper Oxfordian and Kimmeridgian 
species B. reticulata (J. Sowerby) (1821a : 128, pi. 272, fig. 2), which attains a dia- 
meter of 90 mm., has not such a distinct carina at the periphery of its base and its 
spiral ornament is rather more delicate. B. solodurina (Thurmann & Etallon) (1861 : 
129, pi. 11, fig. 102), based on an internal mould 65 mm. in diameter from the Kim- 
meridgian of the Swiss Jura, could possibly be a synonym of B. reticulata. B. neo- 
solodurina (Dacque) (1905 : 141, pi. 16, figs. 5, 6), from the Kimmeridgian of Somali- 
land, is more depressed than the new species now described. 



Superfamily PATELLACEA 

Family uncertain 

Genus PSEUDORHYTIDOPILUS Cox i960 (ex Haber, nom. nud.) 

Pseudorhytidopilus lonjiensis sp. nov. 
PI. 22, figs. 3«, b 

Diagnosis. Outline broadly elliptical, rather flattened anteriorly and posteriorly ; 
moderately large (length of holotype c. 33 mm., breadth c. 28 mm.), well elevated 
(height of holotype c. 16 mm.), with apex situated at about anterior quarter of length 
and directed anteriorly. Ornament consisting of conspicuous concentric growth- 
undulations, about 1 mm. apart. 

Holotype. No. GG.10312. The only specimen. 

Locality and horizon. Along Lonji-Runjo stream at a point x\ miles W. of 
Mandawa, Tanganyika ; Callovian. 



140 JURASSIC BIVALVIA AND GASTROPODA 

Remarks. The genus Rhytidopilus (type-species Patella humbertina Buvignier) 
was founded by Cossmann (1895 : 143) for the reception of certain rather irregularly 
conical internal moulds of shells of Mesozoic age with strong growth undulations and 
a narrow, elevated sector, bordered by furrows, running from the apex to the anterior 
margin. Pseudorhytidopilus includes patelliform shells which are similar to Rhytido- 
pilus except that the raised anterior sector is absent. The species most closely com- 
parable to the one now described is Pseudorhytidopilus arsinoe (d'Orbigny) (figured 
by Thevenin 1913a, pi. 36, figs. 1,2), from the Callovian of France, but in that species 
the apex is more elevated and placed in a less anterior position. Its anteriorly 
pointing and much more forward-placed apex distinguishes the new species from the 
three European Kimmeridgian species P. banneana (Rollier) (1918 : 11, for Patella 
humbertina Thurmann & Etallon 1861, pi. 13, fig. 131, non Buvignier), P. castellana 
(Thurmann & Etallon) (1861, pi. 13, fig. 132), and P. lennieri Cox (i960 : 237, for 
Helcion castellana Lennier 1872, pi. 8 B, figs. 8, 8a). 



Family SYMMETROCAPULIDAE Wenz 1938 

Genus SYMMETROCAPULUS Dacque 1933 

Symmetrocapulus ? sp. 
PI. 22, figs. 5a, b 

1914. IPatella (Fissurella ?) sp. ; Dietrich : 116, pi. 11, fig. 4. 

Material. One specimen (no. G. 48031). 

Locality and horizon. Tingutitinguti creek, Tendaguru, Tanganyika ; Upper 
Kimmeridgian, " Trigonia smeei " Bed. 

Remarks. The specimen now recorded is a small, radially ribbed, patelliform 
shell nearly 9 mm. long. Like the specimens described by Dietrich, as cited above, 
it has lost its apex, so that its generic affinities are uncertain. The apex was evident- 
ly situated within the anterior third of the length of the shell, the dorsal profile rising 
slightly above it posteriorly before curving down to the posterior margin. The 
numerous radial riblets are unequal in breadth and rather irregularly distributed ; 
their intervals are, on the average, of about the same width as the riblets. The whole 
surface, where uneroded, can also be seen to bear fine concentric threads. Dietrich's 
figure appears to represent a specimen with broader and fewer ribs than the present 
one, but the species may be the same. Haber (1932 : 249) suggested the reference 
of Dietrich's form to Symmetrocapulus (then a nomen nudum), but the part of his 
catalogue in which it would have been listed systematically and possibly given a 
specific name was never published. 



FROM TANGANYIKA AND KENYA 141 

Family ACMAEIDAE Carpenter 1857 

Genus SCURRIOPSIS Gemmellaro 1879 

Subgenus DIETRICHIELLA Wenz 1938 

Scurriopsis {Dietrichiella) kindopensis (Dietrich) 
PI. 22, figs. 4a, b 

1914. Patella kindopensis Dietrich : 116, pi. 11, fig. 3. 

1932. Scurria (Dietrichiella) 3 kindopensis (Dietrich) ; Haber : 220. 

1938. Scurria (Dietrichiella) kindopensis (Dietrich) ; Wenz : 219, fig. 405. 

Material. One specimen (no. G. 48913). 

Locality and horizon. Kindope valley, N.W. of Tendaguru, Tanganyika ; 
Upper Kimmeridgian, " Trigonia smeei " Bed. 

Remarks. This small patelliform gastropod, which is 11-3 mm. long and 7-2 mm. 
broad, is a little larger than Dietrich's holotype, but agrees with it in shape and orna- 
ment. The latter consists of concentric rugae and of scarcely perceptible radial 
grooves confined to the neighbourhood of the posterior margin. The apex is placed 
at about one-sixth of the length of the shell from its anterior end, the longitudinal 
profile from it to the posterior end forming an evenly convex curve. 



Superfamily TROCHACEA 

Family TROCHIDAE Rafinesque 1815 

Subfamily PROCONULINAE Cox i960 

Genus AFRICOCONULUS nov. 

Diagnosis. Shell slightly coeloconoid, well elevated, anomphalous ; last whorl 
with two tuberculate or spinose carinae at periphery, the upper and stronger carina 
forming prominent angulation, the lower one just visible at suture on spire whorls; 
remainder of surface ornamented with simple or beaded spiral cords and raised 
collabral threads ; base low, rather flattened ; columellar lip short, simple, describing 
a broad curve abapically to merge with basal lip. 

Type species. Proconulus spinatns Dubar (1948 : 126, pi. 10, figs. 7-9), Middle 
Lias, Morocco. 

Remarks. In this genus the ornament is rather like that of Eucychts, but the 
depressed base and the shape of the aperture indicate that there is no real affinity 
with that subgenus. Dubar was undoubtedly correct in detecting some affinity 
between his species, taken as its type, and Proconulus, but in typical species of that 
genus the whorls lack prominent peripheral carinae and have only weak spiral 
ornament. There is much resemblance between the new genus and Metaconulus 
Cossmann, of the Lower Tertiary, but it is to be assumed that this was due to con- 

3 As published by Haber, this subgeneric name was a nomen nudum. 



i 4 2 JURASSIC BIVALVIA AND GASTROPODA 

vergence. In the Triassic genus Diplochilus Woehrmann, which also has two peri- 
pheral carinae, the aspect of the ornament of the shell is quite different. In Dimor- 
■photectus Cossmann, also founded on a Triassic species, the very short columellar lip 
has a prominent median fold. 

Africoconulus kenyanus sp. nov. 
PI. 30, figs, ga, b, c 

Diagnosis. Rather small (height of largest specimen 14 mm.), trochiform, with 
well elevated, slightly coeloconoid spire ; diameter four-fifths of height ; aperture 
occupying about two-fifths of total height. Spire whorls with a prominent carina 
situated at lower third of their height and bearing prickly tubercles; above the carina 
are two spiral rows of smaller tubercles coinciding with angulations of the surface, 
the upper angulation bordering a narrow sutural ledge. Margin of base formed by 
a second carina which continues the line of the suture ; this carina is slightly less 
prominent than the one above it and bears smaller and more numerous tubercles 
than those on the upper one. The base, which is very little extended, is flattened- 
convex adaxially and is slightly excavated but not umbilicate mesially ; it bears a 
few unevenly distributed spiral cords. In addition, the whole surface of the shell 
bears raised collabral threads which are well separated in some specimens ; threads 
slightly prosocline above main carina and more strongly so below it, while on the base 
some become strengthened adaxially to form transverse riblets. Apertural margin 
imperfect in all specimens. 

Holotype and paratypes. Nos. GG.10250 and GG.10251-57 respectively, 
eight specimens in all. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This species is clearly congeneric with Africoconulus spinatus (Dubar), 
type species of the new genus, but is much smaller and its upper carina has not the 
prominent spines which are present in that species. 



Subfamily ANGARIINAE Thiele 1924 

Genus CHRYSOSTOMA Swainson 1840 

Chrysostoma staffi Dietrich 

PI. 24, figs. la-c 

i<>i4. Chrysostoma Staffi Dietrich : 122, pi. 11, fig. 6. 

Material. One specimen (no. G. 48567). 

Locality and horizon. " Ditch 2x ", Tendaguru, Tanganyika ; just above top 
of lower " Trigonia smeei " Bed, i.e. Upper Kimmeridgian (cf. Parkinson 1930, fig. 3, 
showing horizons near Tendaguru hill). 



FROM TANGANYIKA AND KENYA 143 

Remarks. The specimen now recorded, which is 17 mm. in diameter and 14 mm. 
high, agrees so well with Dietrich's figure that there seems no doubt about its 
specific identity. The spire of the shell is very obtuse, with slightly concave sides, 
and the sutures are scarcely impressed. The last whorl is broadly rounded at the 
periphery and the base is convex, quite uncoated with callus, and narrowly umbili- 
cate. The outer lip is broken away, but the growth-lines are strongly prosocline. 
The aperture, which occupied about five-sixths of the total height of the shell, was 
evidently almost circular. The shell wall is thick and the surface quite smooth. 

This specimen appeared at first sight to belong to the genus Ataphrus, from which 
it differs, however, in its open umbilicus. Dietrich, when describing C. staffi, com- 
mented on its striking similarity to Ataphrus laevigatas (J. Sowerby) (cf. Hudleston 
1894 : 349, pi. 29, figs. 5, 6), of the Inferior Oolite. The holotype was said to come 
from Neocomian beds at a locality near Mikadi, Tanganyika, but the specimen now 
recorded appears to be from an Upper Jurassic horizon. 

Family ATAPHRIDAE Cossmann 1918 

Genus ATAPHRUS Gabb 1869 

Ataphrus aff. actnon (d' Orbigny) 
PI. 24, figs. 2a, b 

1850a. Aff. Trochns Actnon d'Orbigny : 265. 

1853. Aff. Trochns Acmon d'Orbigny : 278, pi. 314, figs. 1-4. 

1885. Aff. Ataphrus Acmon d'Orb. ; Cossmann : 281, pi. 7, figs. 9, 10. 

1894. A.ff. Ataphrus Acmon d'Orbigny ; Hudleston : 351, pi. 29, fig. 11. 

Material. One specimen (no. G. 26204). 

Locality and horizon. Kidugallo, Central Railway, Tanganyika ; Bajocian, 
Station Beds. 

Remarks. This specimen, which is about 9 mm. high, agrees very well with the 
figures of the European Bajocian species A. acmon cited above. Its last whorl and 
aperture, however, are imperfect, so that it seems advisable to qualify its specific 
determination. 



Genus TROCHOPSIDEA Wenz 1938 

Trochopsidea africana sp. nov. 
PI. 24, figs. 5«, b, c, d 

Diagnosis. Shell small (diameter of largest specimen c. 7 mm.), turbiniform, 
diameter exceeding height ; spire obtusely cyrtoconoid, its height almost equal to 
that of the aperture. Whorls smooth, of moderate and even convexity, the last one 
broadly rounded at the periphery. Base evenly convex ; no umbilicus. Inner lip 
with moderatelv wide, grooved outer face, which is limited by a carina and is devoid 
of a tubercle. 



144 JURASSIC BIVALVIA AND GASTROPODA 

Holotype and paratypes. Nos. GG.10258 and GG.10259-62 respectively, five 
specimens in all. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. The characters of the inner lip of this species agree with those of 
Trochopsidea, the presence of the groove on the outer face of this lip distinguishing 
the species from representatives of Ataphrus, which it resembles in its general 
morphology. Turbo garnieri Dumortier (1874 : 139, pi. 35, figs. 15-17), from the 
Upper Lias of southern France, which much resembles the present species except 
that it is slightly more elevated, has not a grooved inner lip and appears to belong to 
Ataphrus (Endianaulax). A specimen from the Upper Lias of Germany identified by 
Kuhn (1935 : 136, pi. 8, fig. 21) as Ataphrus cf. lucidus (Thorent) (a species included 
by Cossmann in the subgenus Endianaulax) is more depressed than the present form. 

Superfamily NERITACEA 

Family NERITIDAE Rafinesque 1815 

Genus NERITOMA Morris 1849 

Subgenus NERIDOMUS Morris & Lycett 1851 

Neritotna (Neridomus) aff. gea (d'Orbigny) 
PI. 24, figs, ya, b 

1852. Aff. Nerita Gea d'Orbigny : 232, pi. 302, figs. 5-7. 

1885. Aff. Nerita Gea d'Orb. ; Cossmann : 155, pi. 3, figs. 1, 2. 

1908. Aff. Nerita gea d'Orbigny ; H. Fischer : 268, pi. 11, figs. 5-12. 

Material. Three specimens (nos. G.61310-12). 

Locality and horizon. S. of Tarawanda, 26 miles W.S.W. of Bagamoyo, 
Tanganyika ; Callovian. 

Remarks. The specimens now recorded, the best of which is just under 10 mm. 
in height and diameter, are characterized by their low spire, obtusely rounded apex, 
and flush sutures. The apex and axis are rather strongly eccentric. The speci- 
mens belong to a group of species which is well represented in the Bathonian of 
Europe and has been discussed by H. Fischer (1908). They seem to be very closely 
comparable to Neritoma (Neridomus) gea, but they are a little larger than the 
specimens figured by the authors cited above, and their axis is more eccentric. 
They are also rather similar in shape to N. (N.) louisiae Fischer (1953 : 15, pi. 1, 
figs. 21-27), also from the French Bathonian, but that species attains a much 
larger size (20 mm.) and has a more pointed apex. Cossmann (1926 : 305, pi. 5, 
figs, la-c) has recorded a specimen of the same group from the Callovian of Sinai 
under the name Neridomus punctatus (Piette), but it is also considerably larger 
than the specimens now recorded. The species Neritodomus sukidugallensis Reck 
(1921 : 435, text-fig. 3) was founded on a small broken shell from the Bajocian 



FROM TANGANYIKA AND KENYA 145 

of a locality along the Central Railway, Tanganyika, and appears to have a more 
prominent apex than the form now recorded. The shell from the Saurian Beds 
of Tendaguru recorded by Dietrich (1914 : 126, pi. n , figs. 10a, b) as Nerita cf. 
transversa v. Seebach var. minor de Loriol differs from the specimens now recorded 
in much the same manner as does N. louisiae. 

Genus LISSOCHILUS Zittel 1882 

Lissochilus stremmei Dietrich 
PI. 24, figs. 4a, b 

1914. Nerita (Lissochilus) Stremmei Dietrich : 126, pi. n, figs. na-e. 

Material. Three specimens (nos. G. 48903, G. 48912, GG.10315). 

Localities and horizons. Kipande, W. of Tendaguru, Tanganyika ; Upper 
Kimmeridgian, Nerinea Beds. Kindope valley, N.W. of Tendaguru ; Upper 
Kimmeridgian, " Trigonia smeei " Beds. i\ miles N.W. of Mandawa, Tanganyika ; 
Upper Kimmeridgian. 

Remarks. In this species a strong rounded carina forms the periphery of the shell 
and a strong, rounded-off angulation marks the boundary of a subhorizontal sutural 
shelf. Below the periphery are several spiral cords, one of which may stand out as a 
keel. Rather irregularly distributed collabral ridges are most conspicuous on the 
later formed part of the last whorl and give rise to tubercles on some of the spirals. 
The two largest specimens now recorded, which are rather eroded, are about 23 mm. 
in diameter. 

Superfamily PALAEOTROCHACEA 

Family PARATURBINIDAE Cossmann 1916 

Genus CHARTRONELLA Cossmann 1902 

Chartronella mitoleensis sp. nov. 
PL 24, figs. 3a, b 

Diagnosis. Shell of medium size, trochiform, with height (19 mm. in the holo- 
type) very slightly exceeding diameter. Whorls bicarinate, the upper carina 
forming the edge of a subhorizontal, slightly concave sutural ledge, the lower, which 
projects abaxially slightly more than the upper one, just exposed above the suture 
on the later whorls and forming the periphery of the base of the shell. Outer face 
of whorls, between the carinae, concave. Base convex, umbilicus absent. Narrow 
spiral cords, with transverse threads crossing their intervals, are present near the 
carinae, but spiral ornament is absent from the remainder of the shell (it could 
conceivably, however, have been removed by erosion in the holotype). Aperture 
almost circular (the outer lip is broken in the holotype) ; a spiral swelling originating 
at the lower margin of the aperture forms the lower border of the convex part of the 
base. 



146 JURASSIC BIVALVIA AND GASTROPODA 

Holotype. No. GG.10313 ; there is no other material except an associated 
internal mould, which scarcely ranks as a paratype. 

Locality and horizon. Mpilipili stream at a point about 1 mile N.E. of Mitole, 
Tanganyika ; Upper Kimmeridgian. 

Remarks. This form resembles the type-species of Chartronella, C. digoniata 
(Cossmann) (1902 : 199, pi. 4, figs. 24-26), from the Hettangian of France, in its 
bicarinate but otherwise almost smooth whorls, in its convex base, and in the absence 
of an umbilicus, but it differs in the fact that the upper of its two carinae marks the 
edge of a subhorizontal ledge instead of a steeply sloping sutural ramp, so that its 
whorls are much lower than in Cossmann's species. 

Family CIRRIDAE Cossmann 1916 

Genus CIRRUS J. Sowerby 1815 

Cirrus mazer asensis sp. nov. 
PL 24, figs. 8a, b 

Diagnosis. Of medium size (original height of holotype, allowing for missing 
last whorl, c. 25 mm. ; height of spire as preserved, c. 15 mm.), sinistral. Spire 
coeloconoid with a very acute apex, and consisting of whorls which are at first almost 
flat but become increasingly convex during growth. Ornament consisting of vari- 
ably but mostly strongly prosocline transverse riblets and of strong concentric 
threads which override them and occupy their intervals ; the ribs, which appear 
close to the upper suture but die out before reaching the lower one, are separated by 
intervals which are almost equal to them in width on the earlier whorls but become 
almost twice as wide on the last preserved whorl ; the spirals number 6 on the later 
whorls and are separated by intervals about twice as wide. Last whorl and aperture 
unknown. 

Holotype. No. GG.6524, an external mould of the spire of the shell from which 
squeezes have been prepared. 

Locality and horizon. Ribe, 9 miles N.E. of Mazeras, Kenya ; Bajocian (?), 
Mazeras Sandstones. 

Remarks. The strongly coeloconoid spire suggests that the last whorl (no longer 
preserved) was umbilicate, so that the species is a Cirrus rather than a Hamusina. 
No species with identical ornament can be traced in the literature. 

Genus HAMUSINA Gemmellaro 1878 

Hamusina thompsoni sp. nov. 
PL 24, figs. 9«, b 

Specific name. After Mr. A. O. Thompson, of the Geological Survey of Kenya. 

Diagnosis. Shell small for the genus (height 11 mm.), acute, sinistral, with 

aperture occupying about one-third of total height ; spire angle c. 30 °. Periphery 



FROM TANGANYIKA AND KENYA 147 

of whorls, situated at about the lower third of their height, formed by an obtuse 
angulation bearing large rounded tubercles, above which the whorl outline is feebly 
concave. Spire whorls ornamented, in addition, with a row of small tubercles 
bordering the upper suture and with very weak spiral threads which are present on 
their entire surface except where removed by erosion. Margin of base formed by a 
narrow, smooth cord continuing the line of the suture ; base ornamented with spiral 
riblets. Aperture circular (its margin is imperfect). 

Holotype. No. GG. 10263. The only specimen. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This small shell is unquestionably congeneric with Turbo bertheloti 
d'Orbigny, the type species of Hamusina, but it differs from that species in obvious 
details of ornament. No species very closely comparable to it is described in the 
literature. 

Superfamily SUBULITACEA 

Family PSEUDOMELANIIDAE Fischer 1885 

Genus PSEUDOMELANIA Pictet & Campiche 1862 

Pseudomelania aspasia (d'Orbigny) 
PI. 24, fig. 10 

1850a. Chemnitzia Aspasia d'Orbigny : 298. 

1851. Chemnitzia Aspasia d'Orb. ; d'Orbigny : 49, pi. 242, fig. 4. 

1 85 1. Chemnitzia niortensis d'Orbigny : 48, pi. 242, figs. 1, 2. 

1885. Pseudomelania niortensis (d'Orb.) ; Cossmann : 172, pi. 9, figs. 6, 7. 

Material. One shell (no. GG.10317). Two incomplete internal moulds may also 
belong to the species. 

Localities and horizons. Shell-bearing specimen from Nchia stream, 2 miles 
W.N.W. of Mandera, Tanganyika ; internal moulds from Lonji stream, E.N.E. of 
Nandenga, Tanganyika ; Callovian. 

Remarks. The shell-bearing specimen agrees so closely with the figures of P. 
aspasia published by d'Orbigny and by Cossmann that I see no reason to qualify its 
specific determination. The species occurs typically in the Bathonian of France. 
In P. caecilia (d'Orbigny) (1851 : 64, pi. 248, fig. 2 ; de Loriol 1874 : 331, pi. 8, 
figs. i«, b), from the Lower Kimmeridgian of France, and P. laufonensis Thurmann 
& Etallon (1861 : 88, pi. 6, fig. 27), a Swiss species of about the same age, the spire 
angle is about the same but the whorls are quite flat. 

On the internal moulds now recorded there is a tendency for a spiral groove to be 
developed low on the side of the whorl, just above the lower suture. As it is dis- 
continuous it does not appear to represent a spiral fold on the interior of the whorls 
and it may have arisen by deformation of the internal mould after the shell had 
disappeared in solution. 



148 JURASSIC BIVALVIA AND GASTROPODA 

Pseudomelania dusseensis sp. nov. 
PI. 24, figs. 11a, b, c 

Diagnosis. Shell small (height about 11 mm.), regularly conical, moderately 
acute (spire angle about 16 °), with the spire formed of rather low, very feebly convex 
(virtually flat) whorls, separated by flush sutures ; height of spire whorls equal to 
about one-half of their diameter. Last whorl abruptly rounded, almost angular at 
periphery ; base low, feebly convex, without umbilicus. Aperture broader than 
high ; outer lip flat or very feebly convex ; columellar lip short. Surface smooth ; 
growth-lines, where faintly visible, arched, with a shallow forward-facing concavity. 

Holotype and paratypes. Nos. 0.76399 and G.76400-02 respectively, four 
specimens in all. 

Locality and horizon. Low hills at Dusse, ij miles S.E. of Rahmu, N.E. 
Kenya ; Upper Oxfordian, Seir Limestones. 

Remarks. This species closely resembles Pseudomelania communis (Morris & 
Lycett) (1851 : 48, pi. 9, figs. 21, 21a), from the English Bathonian, but is distin- 
guished by its flatter whorls. P. laubei Cossmann (1885 : 176, pi. 11, figs. 32, 33 ; 
pi. 15, fig. 47), from the Bathonian of France, is a larger shell (25 mm. high), with 
slightly higher whorls. In the French Callovian species P. calloviensis (Hebert & 
Deslongchamps) (Couffon 1919 : 126, pi. 8, figs. 19-19^ ; Cossmann 1924 : 4, pi. 1, 
figs. 21-23) the whorls are relatively higher. P. calloviensis has axial riblets on its 
earliest formed whorls and therefore belongs to the subgenus Hudlestoniella Coss- 
mann. As the corresponding whorls are missing on the specimens now described it 
is not possible to say if the species should be included in that subgenus rather than in 
Pseudomelania s. str. Of European Oxfordian species, P. ebersteini (Thurmann) (de 
Loriol 1899 : 133, pi. 9, fig. 20), from the Swiss Jura, is a broader shell than the form 
now described and has more strongly convex whorls. 

Pseudomelania vittata (Phillips) 
PI. 24, fig. 12 

1829. Melania vittata Phillips : 145, pi. 7, fig. 15. 

1863. Chemnitzia vittata (Phil.) ; Lycett : 14, pi. 31, fig. 10. 

1882. Chemnitzia vittata (Phil.) ; Hudleston : 244, pi. 6, figs. 5a, b, 6. 

1905. Pseudomelania vittata (Phil.) ; Blake : 77, pi. 8, figs. 1, 2. 

1950. Pseudomelania vittata (Phillips) ; Cox & Arkell : 62. 

Material. One specimen (no. GG.10316). 

Locality and horizon, i mile N. of Manyuli, Tanganyika ; Upper Kim- 
meridgian. 

Remarks. Pseudomelania vittata is a large form characterized by the presence 
on the last whorl of two strong but obtuse keels, between which the face of the shell 
is slightly concave. On the spire whorls the upper keel lies at about the posterior 
third of the height, while the lower keel may or may not be visible near the lower 
suture, according to the degree of whorl overlap. I am unable to distinguish the 



FROM TANGANYIKA AND KENYA 149 

East African specimen from those from England, where, however, the species seems 
to be confined to the Cornbrash (Upper Bathonian-Callovian). The original length 
of this specimen was about 120 mm., but it now lacks the apical whorls. 

In the well-known species P. heddingtonensis (J. Sowerby), of the Upper Oxfordian 
and Lower Kimmeridgian of Europe, the size and proportions of the shell are much 
the same as in the specimen now recorded, and in some specimens there is a slight 
spiral swelling of the whorl face in the same position as the upper carina of P. vittata. 
The outer face of the whorl is, however, convex and there is no carina at the per- 
iphery of the base. Hudleston (1882 : 245) commented on the doubtful value of 
the specific distinctions drawn between a number of Jurassic " Chemnitzias ", 
but thought that the slight differences noted might depend upon the geological 
horizon. It is evident from the occurrence now recorded that the differences 
between P. vittata and P. heddingtonensis have no stratigraphical significance. 

Of other Upper Jurassic species of the group now described, P. sulcata (Zieten) 
(Brosamlen 1909 : 283, pi. 21, fig. 15), from the Kimmeridgian of Nattheim, southern 
Germany, and a series of forms from France (P. athleta, P. pollux, P. columna, P. 
domoisii, etc.) illustrated by d'Orbigny (1851, pis. 245-248), all, like P. heddington- 
ensis, differ from P. vittata in lacking the lower of the two carinae on the last whorl. 



Subgenus OONIA Gemmellaro 1878 

Pseudomelania (Oonia) kidugalloensis sp. nov. 
PL 26, figs. 4a, b, c 

Diagnosis. Shell of medium size for the genus (height of holotype 10-4 mm.), 
phasianelliform, height of aperture about three-sevenths of that of shell ; spire 
angle about 40°. Protoconch unknown complete. Spire whorls strongly convex, 
about twice as broad as high, abutting simply at the sutures ; last whorl evenly 
convex at periphery. Base also evenly convex in outline, not much extended, 
without umbilicus. Aperture obliquely oval, its height nearly twice its breadth. 
Columellar lip short, apparently joining basal margin of aperture in an even curve. 
Outer lip almost orthocline ; details of parietal region not well seen. Growth-lines 
obscure. 

Holotype. No. GG. 10280. The only specimen. 

Locality and horizon. 2| miles N.N. W. of Kidugallo, Tanganyika ; Bajocian. 

Remarks. This species seems closely comparable to the English Bajocian species 
" Phasianella " latiuscula Morris & Lycett, as figured by Hudleston (1891 : 251, pi. 
19, figs. 10a, b), but its spire occupies a relatively greater proportion of the height of 
the shell than in that species and it is much smaller. The English species is included 
in Pseudomelania {Oonia) by Cox & Arkell (1950 : 97). 



150 JURASSIC BIVALVIA AND GASTROPODA 

Pseudomelania (Oonia) conica (Morris & Lycett) 
PI. 25, figs. 2a, b, c 

1 85 1. Phasianella conica Morris & Lycett : 74, pi. n, figs. 30, 30a. 

1851. Phasianella acutinscula Morris & Lycett : 75, pi. 9, fig. 2 ; pi. 11, figs. 28, 28a (non 

Lycett 1850). 
1885. Phasianella acutinscula Morris & Lycett : Cossmann : 253, pi. 9, fig. 18 ; pi. 17, figs. 

22, 23. 
1900. Phasianella ? acutiuscula Morris & Lycett ; Cossmann : 571, pi. 17, fig. 19. 
19076. Phasianella ? acutiuscula Morris & Lycett ; Cossmann : 253, pi. 7, fig. 5. 

Material. One specimen (no. GG. 10463). 

Locality and horizon. 2 miles W. of Tengeni (village on Pangani river), in 
Mbuzi Mkubwa stream, Tanganyika ; Bathonian (?). 

Remarks. The specimen, which is 21-5 mm. high, agrees well with some speci- 
mens from the Great Oolite of England, although it is slightly more slender than those 
figured by Morris and Lycett. The sutures are flush and the spire is slightly 
cyrtoconoid. Another Bathonian species, P. (0.) variata (Lycett 1863 : 104, pi. 45, 
figs. 28, 28a, b), especially as figured by Cossmann (1885 : 255, pi. 4, fig. 52 : pi. 11, 
fig. 17), is also of much the same proportions as the shell now recorded, but its sutures 
are more impressed and its base is less extended. 



Pseudomelania (Oonia) dietrichi sp. nov. 
PL 24, figs. 6a, b 

1914. Pseudomelania (Oonia) aff. Sancti Antonii (Struckmann) ; Dietrich : 129, pi. 11, figs. 
ija-c. 

Diagnosis. Shell of medium size (height of holotype 34 mm.), of moderate acute- 
ness (spire angle about 30 °) ; aperture occupying about three-sevenths of total 
height. Whorls strongly and evenly convex, their mean height equal to about one- 
half of their diameter. Ornament consisting of faint spiral striae together with 
growth rugae which are strongly pronounced on the last whorl and are slightly arched, 
with a backward-facing convexity. 

Holotype and paratypes. Nos. G. 48028 and G. 48021-27 respectively, eight 
specimens in all. 

Locality and horizon. Tingutitinguti creek, Tendaguru, Tanganyika ; Upper 
Kimmeridgian, " Trigonia smeei " Bed. 

Remarks. A search through the literature has confirmed Dietrich's conclusion 
that the most closely comparable species previously described is Chemnitzia Sancti 
Antonii Struckmann (1878 : no, pi. 7, figs. 2a, 6,3), from the Kimmeridgian of Ahlem, 
near Hanover. In the species in question, however, the shell is slightly more acute 
than in the Tendaguru shell and a fine reticulate ornament is present, in which the 
spiral threads are slightly more prominent than the collabral ones, whereas in the 
East African form the spiral lines are scarcely visible to the unaided eye and much 



FROM TANGANYIKA AND KENYA 151 

weaker than the collabral rugae. Another comparable European species is P. 
collisa de Loriol (1874 : 334, pi. 7, figs. 30, 31), from the Lower Kimmeridgian of 
France, but its whorls are slightly more convex than those of the form now described. 



Pseudomelania {Oonia) aitkeni sp. nov. 
PL 25, figs, ia, b, c 

Specific name. After Dr. W. G. Aitken, lately Director of the Geological 
Survey of Nyasaland, and collector of the holotype. 

Diagnosis. Shell of medium size (height of holotype c. 22 mm.), ovate-conical, 
with diameter equal to about one-half of height. Spire slightly coeloconoid, with 
very acute apex. Spire whorls low, their mean height rather less than one-third of 
their diameter, feebly convex, the later ones with a narrow, ill-defined sutural ledge. 
Last whorl broadly and evenly convex at periphery, outline of base scarcely exca- 
vated ; no umbilicus. Aperture oval, originally occupying about one-half of total 
height of shell (its margin, however, is broken away in the holotype). Surface 
smooth. 

Holotype. No. GG.10318. The only specimen. 

Locality and horizon. Along Mandawa-Namakongoro stream, about 1 mile 
W. of Mandawa, Tanganyika ; Middle-Upper Kimmeridgian. 

Remarks. As the apertural margin is broken away in the holotype it is not 
possible to observe if (as in the Pseudomelaniidae) it was uninterrupted anteriorly 
or if (as in some Coelostylinidae) a small notch or sinus was present at the foot of the 
columella. The species is here referred to the pseudomelaniid subgenus Oonia, from 
the typical species of which it differs in its aciculate apex. It is of about the same 
size and proportions as Pseudomelania (Oonia) recki Dietrich (1914 : 130, pi. n, 
figs. 16a, b), from Tendaguru, but is readily distinguished by its coeloconoid spire 
and more numerous and flatter whorls. In P. (0.) cornelia (d'Orbigny) (1851 : 60, 
pi. 245, figs. 2, 3), from the " Corallian " of the Ardennes, and in P. (0.) quirandi de 
Loriol (1887 : I 45> P 1 - I 5. n g s - 5- °)> from the Lower Kimmeridgian of Valfin (Jura), 
the spire is slightly cyrtoconoid and the last whorl is less inflated. P. (0.) daphne 
de Loriol (1890 : 87, pi. 11, fig. 6), from the Upper Oxfordian of the Bernese Jura, 
is a smaller shell. 

Subgenus RHABDOCONCHA Gemmellaro 1878 

Pseudomelania (Rhabdoconcha) wilder riensis sp. nov. 
PL 25, fig. 10 

i960. Pseudomelania valfinensis de Loriol ; Joubert, pi. 11, fig. 13& (non de Loriol). 

Diagnosis. Shell large (original height of holotype c. 120 mm.), acute (spire 
angle 12 °), with feebly and evenly convex whorls the height of which is about three- 
quarters of the diameter ; last whorl broadly convex at periphery. Surface orna- 



15-2 JURASSIC BIVALVIA AND GASTROPODA 

mented with numerous fine spiral striae ; growth-lines forming a simple, shallow 
arch the chord of which is moderately prosocline. (The aperture is not preserved 
intact.) 

Holotype. No. G. 76414. The only specimen. 

Locality and horizon. Wilderri hill, 11 miles S.S.W. of Rahmu, N.E. Kenya ; 
Upper Oxfordian, Seir Limestones. 

Remarks. When first illustrated, the shell now described was identified as 
Pseudomelania valfinensis de Loriol (1887 : 141, pi. 14, fig. 7). Its spiral ornament, 
which is clearly seen on parts of the holotype (although the surface is rather eroded), 
resembles that of this European Lower Kimmeridgian species, but its spire is more 
acute. 

Genus BOURGUETIA Terquem & Jourdy 1870 

Bourguetia saemanni (Oppel) 
PL 25, figs. 8, 9 

1814a. Melania striata J. Sowerby : 101, pi. 47 (non Perry, 181 1). 

1853. Phasianella striata (Sow.) ; d'Orbigny : 322, pi. 324, fig. 15, pi. 325, fig. 1. 

1856. Phasianella saemanni Oppel : 507. 

1881. Bourguetia striata (Sow.) ; de Loriol : 31, pi. 8, fig. 5. 

1905. Bourguetia striata (Sow.) ; Dacque : 143. 

1909. Bourgouetia (sic) striata (Sowerby) ; Brosamlen : 284. 

1938. Bourguetia saemanni (Oppel) ; Cox : 60. 

i960. Bourguetia saemanni (Oppel) ; Joubert, pi. 12, figs, za, b. 

Material. Several specimens. 

Localities and horizons. Nchia stream, 2 miles W.N.W. of Mandawa, Tangan- 
yika ; Callovian. Scarp face, eastern margin of Makoko plain, Bagamoyo hinter- 
land, Tanganyika ; Upper Oxfordian. Low hills at Dusse, i\ miles S.E. of Rahmu, 
N.E. Kenya ; Upper Oxfordian, Seir Limestones. Wilderri hill, 11 miles S.S.W. 
of Rahmu ; same formation as the last. Hereri river crossing, 3 miles S. of Melka 
Kunha, N.E. Kenya ; Kimmeridgian, Hereri Shales. 

Remarks. The occurrence in East Africa of this well-known large European 
Jurassic shell, already recorded from the Kimmeridgian of Somaliland by Dacque, is 
of great interest. In Europe the range of this species is from the Bajocian to the 
Lower Kimmeridgian. 

Family COELOSTYLINIDAE 

Genus COELOSTYLINA Kittl 1894 

Coelostylina stockleyi sp. nov. 
PL 26, figs. 3a, b, c 

Specific name. After Mr. G. M. Stockley, formerly Director of the Geological 
Survey of Tanganyika. 



FROM TANGANYIKA AND KENYA 153 

Diagnosis. Shell of medium size for the genus (original height of holotype c. 12 
mm.), phasianelliform, height of aperture about two-fifths of that of shell ; spire 
angle about 35 °. Protoconch unknown (broken off in holotype). Spire whorls 
rather high, moderately convex, abutting simply at the sutures ; last whorl broadly 
convex at periphery. Base evenly convex in outline, not much extended ; no 
clearly open umbilicus is seen, but a small cleft in the base of the holotype may be 
the opening of a very narrow one. Aperture ovate, angular posteriorly, not oblique. 
Columellar lip straight and vertical although not much extended, slightly undercut 
by a well-marked sinus which separates it from the basal margin of the aperture. 
Outer lip orthocline ; details of parietal region not well seen in available specimen. 
Growth-lines obscure. 

Holotype. No. GG.10281. The only specimen. 

Locality and horizon. z\ miles N.N.W. of Kidugallo, Tanganyika ; Bajocian. 

Remarks. The apertural characters of this species and of the one described next 
agree with those of members of the family Coelostylinidae rather than with those of 
the pseudomelaniid subgenus Oonia, which they greatly resemble in the general 
morphology of the shell. The only Bajocian and at the same time the geologically 
youngest representative of the family hitherto recognized, is Coelostylina brasili 
Cossmann (19136 : 217, pi. 8, figs. 58, 59), from France. This form is more than 
twice the height of the species now described and has a less distinct sinus at the foot 
of its columella. Cossmann pointed out that certain species from the Bajocian of 
England described by Hudleston (1891 : 251-255, pi. 19, figs, n-15) under the 
generic name Phasianella might well belong to Coelostylina. Specimens identified 
by him (1891, pi. 19, figs. 11a, b, 14b) as Phasianella elegans Morris & Lycett (a 
Bathonian Oonia) are very similar to the African species now described. 

Coelostylina mandawaensis sp. nov. 
PL 25, figs. 4a, b, 5a, b, 6a, b, ya, b 

Diagnosis. Shell of medium size for the genus (height of largest specimen 13 
mm.), ovate-conical, aperture occupying rather less than one-half of total height. 
Protoconch minute, dome-like. Spire slightly cyrtoconoid, acute, consisting of 
feebly to moderately convex whorls abutting simply at the sutures ; last whorl 
broadly rounded at periphery. Base extended, evenly convex in outline ; no clearly 
open umbilicus is seen, but a small median cleft in the base may be the opening of a 
very narrow umbilicus. Aperture much higher than broad. Columellar lip ex- 
tended, straight and vertical or leaning slightly to the left adapically and joining the 
basal margin in a very abrupt curve, the junction forming a slight beak-like pro- 
tuberance. Margin of columellar lip narrowly reflected, partly covering umbilical 
cleft and continued across parietal region by margin of a thin inductura which passes 
beneath the outer lip. Growth-lines prominent on last whorl, prosocline near the 
suture, orthocline below. 

Holotype and paratypes. Holotype, no. GG. 10283. Numerous paratypes, 
including nos. GG. 10284-86. 



154 JURASSIC BIVALVIA AND GASTROPODA 

Localities and horizon. Near site of Mandawa well no. i, Tanganyika (type- 
locality). Mandawa well no. 6, Tanganyika, at depths 58-60 feet, 60-62 feet, 62-64 
feet, 64-66 feet, 66-68 feet. Lihimaliao creek, at a point near Mbaru creek, Man- 
dawa area, Tanganyika (a specimen preserved in matrix adherent to a crushed speci- 
men of Protocardia bipi). All Bajocian (?), 

Remarks. There has been some difference of opinion as to the distinction be- 
tween Coelostylina and Omphaloptycha , a genus founded by von Ammon two years 
earlier. According to the criteria accepted by Cossmann (1909 : 47), the species 
now described might appear better referable to Omphaloptycha, its ovate-conical form 
and the feeble convexity of its whorls distinguishing it from the type-species of 
Coelostylina. Nevertheless, in a later work Cossmann (1913& : 211-218, pi. 15) 
refers a number of species, very much like the African shell, to Coelostylina. I think 
it undesirable to separate this form generically from C. kidugalloensis sp. nov., des- 
cribed above, and I therefore also include it in Coelostylina. It differs from C. 
kidugalloensis in its less convex whorls and its more extended and relatively narrower 
aperture. 

Superfamily LOXONEMATACEA 
Family ZYGOPLEURIDAE Wenz 1938 
Genus ZYGOPLEURA Koken 1892 



Zygopleura mandawaensis sp. nov. 
PL 25, figs. 3a, b, 11 



Diagnosis. Shell rather small (height of largest specimen about 12 mm. when 
complete), acute ; spire angle abut 15°. Protoconch finely pointed. Whorls with 
an imbricate appearance, due to presence of an obtuse angulation at about the lower 
quarter of their height, above which their outline is flattened ; the angulation forms 
the periphery of the last whorl. Ornament consisting of strong, rounded collabral 
costae separated by intervals of about the same width ; in some specimens the costae 
are opisthocyrt for the whole of their exposed length, while in others they are para- 
sigmoid, with the part above the angulation opisthocyrt and the part below proso- 
cline. On the penultimate or the last whorl the costae fade away, so that the surface 
bears only collabral threads or rugae. Base smooth, feebly convex to almost flat in 
outline. Outer lip with broad sinus corresponding to opisthocyrt part of costae. 

Holotype and paratypes. Holotype, no. GG.10287 (ex B.P. Coll.), a specimen 
associated with the holotype of Ceratomya tanganyicensis, sp. nov. There are several 
paratypes, including nos. GG. 10288-89, none complete. 

Localities and horizon. Lihimaliao creek traverse, Mandawa area, Tangan- 
yika (type-locality). Mandawa well no. 6, Tanganyika, at the following depths : 
58-60 feet, 60-62 feet, 62-64 feet, 64-66 feet. Near site of Mandawa well no. 1. 
All Bajocian (?). 

Remarks. The Middle Jurassic species of Zygopleura so far described are relatively 
large forms, 50-100 mm. in height, and it is necessary to turn to the Lias to find any 



FROM TANGANYIKA AND KENYA 155 

species with which the present one could be brought into comparison. Z. subrugosa 
McDonald & Trueman (1921 : 330, text-fig. 18), from the Upper Lias of Grantham, 
Lincolnshire, resembles the East African species in its angular whorl profile and does 
not greatly exceed it in height, but it is a less acute shell, the periphery of its whorls is 
much more protruding, and the number of costae on each whorl is greater. 



Superfamily LITTORINACEA 

Family PURPURINIDAE Zittel 1895 

Genus PURPUROIDEA Lycett 1848 

Purpuroidea supraliasica sp. nov. 
PI. 28, figs. 4a, b 

Diagnosis. Shell rather small for the genus (height of largest specimen c. 30 
mm.), conical-ovate, diameter two-thirds of height, spire elevated, acute, occupying 
up to one-half of total height. Whorls with almost flat sides, slightly convergent 
adapically, separated from narrow sutural ramp by shoulder bearing large rounded 
tubercles. Base extended, slightly convex in outline, and limited by an obtuse, 
rounded-off angulation that continues the line of the suture. Parietal lip straight, 
oblique, with a narrow, distinctly margined layer of callus, and joining the apparently 
very short columellar lip (not preserved complete in the available specimens) in an 
obtuse angle. Outer lip not preserved in the available specimens, in which any finer 
ornament that may have been present has been obliterated by erosion. 

Holotype and paratypes. Nos. GG.10264 and GG.10265-69 respectively, six 
specimens in all. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. This shell is comparable in shape to the much larger species Purpuroi- 
dea berberica Dubar (1948 : 94, pi. 7, figs. 6-8), from the Middle Lias of Morocco, 
and has a similar tuberculate shoulder to its whorls. Its base, however, is more 
extended than in that species. 

Purpuroidea aff. gigas (Thurmann & Etallon) 
PI. 26, fig. 2 ; PI. 27, fig. 15 

1861. Aff. Purpura gigas Thurmann & Etallon : 138, pi. 13, fig. 121. 

1874. ?Aff. Purpurina subnodosa (Roemer) ; Brauns : 169 (non Natica? subnodosa Roemer). 

1881. Aff. Purpuroidea gigas (Etallon) ; Schlosser : 68, pi. 10, figs. 4, 4a. 

1909. ?Aff. Purpuroidea subnodosa (Roemer) ; Brosamlen : 251 {non Roemer sp.). 

Material. One specimen (no. GG. 10328). 

Locality and horizon, £ mile N.W. of Mbinga, Tanganyika ; Upper Kim- 
meridgian. 



156 JURASSIC BIVALVIA AND GASTROPODA 

Remarks. The specimen now recorded is a large internal mould, 153 mm. high. 
Its apical whorls are broken away, but the original height of its spire may be esti- 
mated as 60 mm. The maximum diameter of the last whorl is about 130 mm. 
The last whorl has a rounded-off shoulder bearing large blunt tubercles, about nine 
in number, and above the shoulder is a sutural ramp of steadily increasing breadth 
which eventually forms an angle of about 45 ° with the axis of the shell. The 
tubercles and ramp are not seen on the mould of the earliest preserved whorls. The 
outer face of the last whorl is of feeble convexity and more or less vertical, its outline 
merging in a broad curve into that of the base, which is strongly excavated at the 
beginning of the short neck of the specimen. It is improbable that an umbilicus 
was present in the original shell. 

Schlosser (1881) placed Natica} subnodosa Roemer (1836 : 157, pi. 10, fig. 10) in 
the synonymy of Purpuroidea gigas but did not adopt the earlier of the two specific 
names. Brosamlen (1909) accepted this synonymy and adopted Roemer's name. 
Examination of Roemer's figure of N.} subnodosa, however, raises considerable doubt 
as to whether this represents a Purpuroidea at all. It illustrates a specimen with a 
wide, flat sutural ledge, separated by a sharp, obscurely nodose angulation from the 
vertical outer face of the whorl. No difference in the thickness of the wall of the 
shell would produce a difference in the form of the internal mould comparable to 
that between Roemer's figure and the illustrations of P. gigas given by Thurmann & 
Etallon and by Schlosser. Moreover, I have recently had occasion to study a speci- 
men from the Jurassic of Tunisia resembling Roemer's figure of Natica} subnodosa. 
The specimen in question recalls the Hettangian species Ampullaria carinata Ter- 
quem, which Cossmann (19136 : 174, pi. 9, figs. 14-17) has included in the genus 
Tretospira Koken. It may, therefore, be suggested that Roemer's figure represents 
a specimen belonging to that genus. Unfortunately, no specimens from northern 
Germany of the species which Brauns records as Purpurina subnodosa (Roemer) and 
states is characteristic of the Kimmeridgian are available to me, but it is to be sus- 
pected that its identification with Roemer's species is incorrect. Brauns states that 
specimens of the species reach a height of 180 mm. and a diameter of 150 mm. The 
specimen from East Africa now recorded agrees quite well with the illustrations of 
P. gigas given by the authors cited, but it seems desirable to qualify its specific 
determination. 

Superfamily CERITHIACEA 
Family PROCERITHIIDAE 

Genus PROCERITHIUM Cossmann 1902 
Subgenus RHABDOCOLPUS Cossmann 1906 

Procerithium (Rhabdocolpus) mandawaense sp. nov. 

PI. 27, figs, ga, b, 10a, b, 11a, b, 12a, b 

Diagnosis. Shell of medium size for the subgenus (height of largest specimens, 
when complete, c. 8 mm.) ; spire angle varying from about i5°-20°. Protoconch 



FROM TANGANYIKA AND KENYA 157 

elevated, acute, of about z\ smooth whorls. Succeeding whorls with fiat to feebly 
concave outer face and broad, angularly impressed sutural region. Ornament con- 
sisting of collabral ribs which extend right across the whorls except for the impressed 
sutural region, and are overridden by spiral threads. Collabral ribs narrow but 
moderately strong, straight or opisthocyrt to a varying extent, numbering 10-12 on 
the later whorls, and separated by intervals about twice their width. Spiral threads 
on spire whorls most commonly 5, more rarely 6 or even more, one forming each 
border of the sutural depression ; in some specimens they are almost equal in 
strength and evenly distributed, while in others they are unequal, alternating in 
strength or quite irregularly arranged. Small granules situated at intersections of 
collabral ribs and spiral threads are present on uppermost and lowest of the latter in 
most specimens, but in a few specimens on uppermost only, and in some on inter- 
mediate threads also ; strongest granules pointed, majority rounded. Base evenly 
convex, ornamented with strong spiral threads. Aperture (broken in most speci- 
mens) apparently evenly rounded. 

Holotype and paratypes. Holotype, no. GG. 10290, ex B.P. Coll. Many 
paratypes, including nos. GG. 10291-93. 

Localities and horizons. Mandawa well no. 6, Tanganyika, at the following 
depths : 38-40 feet, 44-46 feet, 46-48 feet (very common), 48-50 feet, 50-52 feet 
(common), 52-54 feet, 56-58 feet, 58-60 feet, 60-62 feet, 62-64 feet, 64-66 feet, 66- 
68 feet, 68-70 feet. Mandawa well no. 7, depth 92-100 feet. Bajocian (?). 

Remarks. The muricate type of ornament present in this species is found in both 
the subgenera Rhabdocolpus and Xystrella, although in the more typical species of the 
latter such ornament is more coarsely developed. According to Cossmann the most 
important distinction between the two subgenera is that the aperture is rounded in 
Rhabdocolpus and quadrangular in Xystrella ; hence, if this criterion is accepted, the 
species now described must be included in Rhabdocolpus. Its ornament differs in 
detail from that of any described European species. 

Genus EXELISSA Piette i860 

Exelissa africana sp. nov. 
PL 27, figs. 2a, b, 3a, b, 4a, b, $a, b 

Diagnosis. Of medium size for the subgenus (height of largest specimens about 
8 mm.), conical to cyrtoconoid, acute, mean spire angle most commonly about 10 °. 
Protoconch finely pointed. Whorls high, tending to be loosely coiled, with flat to 
feebly convex outer face and wide, well impressed sutural region. Ornament consist- 
ing of collabral ribs overridden by spiral threads. Collabral ribs confined in many 
specimens to adapical half of whorls and strongest near the suture, but stretching in 
some specimens from suture to suture, prosocline, straight to rather strongly opistho- 
cyrt ; their number, breadth and distance of spacing varying in different specimens. 
Spiral threads 8-10 or more on later whorls, subequal to distinctly unequal, present 
on the entire surface, although least conspicuous near the adapical suture when the 
collabral ribs there are strong. When the collabral ribs are well developed small 



158 JURASSIC BIVALVIA AND GASTROPODA 

tubercles are present where the ribs are crossed by spiral threads. Base evenly 
convex, ornamented only with strong spiral threads. Last whorl tending to become 
slightly disjunct, deviated, and narrower in cross-section just before the aperture. 
Aperture almost circular, but extending obliquely below the foot of the columella, so 
that the inner lip is situated well to left of axis of shell. 

Holotype and paratypes. Holotype, no. GG.10295, ex B.P. Coll. About 50 
paratypes (mostly imperfect) including nos. GG. 10294, GG. 10296-97. 

Localities and horizon. Mandawa well no. 6, Tanganyika, at depths 50-52 
feet, 52-54 feet, 54-56 feet, 56-58 feet, 58-60 feet, 66-68 feet, 68-70 feet, 70-72 feet. 
Near site of Mandawa well no. 1. All Bajocian (?). 

Remarks. This species could be described as an Exelissa with the ornament of a 
Rhabdocolpus. It is probable that Exelissa is a polyphyletic genus, its various spe- 
cies, characterised by the disjunct and deviated condition of the last whorl just before 
it reaches the aperture, having been derived independently from various groups of 
Procerithium. The taxonomic implications of this theory cannot, however, be ex- 
plored here. After careful study of the series of specimens now described, the con- 
clusion has been reached that they all belong to the same species, although the outline 
of the whole shell and of individual whorls varies considerably and the Exelissa con- 
dition of the apertural region of the last whorl seems to be more marked in some 
specimens than in others. 

Exelissa dodsoni sp. nov. 
PI. 26, figs. la, b 

Specific name. After Mr. R. G. Dodson, of the Geological Survey of Kenya, 
collector of the type-specimens. 

Diagnosis. Shell of medium size for the genus (usual height 6-7 mm.), conical 
or slightly cyrtoconoid, spire angle about 15 °. Protoconch elevated, acute, but 
eroded in available specimens, so that the number of whorls forming it is uncertain. 
Teleoconch whorls with flat outer face and broad, well impressed sutural region. 
Ornament consisting of collabral ribs overridden by spiral threads. Collabral ribs 
on most whorls narrow but prominent, orthocline or slightly prosocline, separated by 
slightly broader intervals, and extending right across the outer face of the whorl, their 
upper end projecting at the impressed sutural region ; they number about 12 on the 
later whorls on which they are developed. On the later whorls, however, especially 
the last, the lower half of each rib, or even the whole rib, tends to be only faintly 
developed. Spiral threads 6-7 in number on the spire whorls, where they are mostly 
unequal in strength and extend on to the sutural depression. Small granules may be 
present at the intersections of the spiral and collabral elements, particularly on the 
thread forming the lower border of the sutural depression. Last whorl tending to 
become narrower in cross-section and slightly disjunct just before the aperture. 
Base evenly convex, ornamented with spiral threads. Aperture oval, broader than 
high, extending obliquely below the foot of the columella, so that the inner lip is 
situated well to the left of the axis of the shell. 



FROM TANGANYIKA AND KENYA 159 

Holotype and paratypes. The type material consists of numerous specimens 
preserved in relief (but in many cases in an eroded condition) on a bedding plane of a 
piece of hard limestone registered as no. G. 79190. A specimen represented in PI. 26, 
fig. 16 (middle of left-hand side of figure) is taken as holotype. 

Locality and horizon. Hagardulun, 25 miles N.E. of Tarbaj, N.E. Kenya ; 
Bathonian-Callovian, Bur Mayo Limestones. 

Remarks. This species was originally recorded (Thompson & Dodson i960 : 32) 
as Procerithium (Rhabdocolpus) sp. The same remark applies to it as to Exelissa 
africana, described above ; it is an Exelissa (as determined by the characters of the 
aperture) with the ornament of a Rhabdocolpus. It is less slender than E. africana 
but more strongly ribbed. The general form of the shell and the ornament are 
much more similar to those of Procerithium {Rhabdocolpus) mandawaense, also des- 
cribed above, but its costae are rather more numerous and, generally, straighter 
than in that species and it has a greater number of spiral threads. Enough can be 
seen of the apertural characters of P. mandawaense to show that it cannot be in- 
cluded in Exelissa. 



Genus PARACERITHIUM Cossmann 1902 

Paracerithium lonjiense sp. now 

PL 27, figs. 6a, b, 13a, b 

Diagnosis. Shell small (height of holotype 3-5 mm.), rather stoutly conical, spire 
angle about 38 °. Protoconch conical, with its initial whorl minute. Early whorls 
evenly convex, later whorls with a well-marked shoulder separating a concave sutural 
ramp, which meets the preceding whorl almost tangentially, from a feebly convex 
outer face which on the later whorls is inclined inward abapically and on the last 
whorl merges in an even curve with the moderately convex base. Ornament con- 
sisting of strong, rounded collabral ribs which tend to form tubercles at the shoulder 
on the last whorl and are crossed by spiral cords (one at the shoulder and two on the 
outer face) separated by much broader intervals ; the base bears only spiral cords 
which are more closely spaced than those on the remainder of the surface. Aperture 
not preserved intact. 

Holotype and paratypes. Holotype, no. GG. 10298, ex B.P. Coll. ; several 
paratypes (including no. GG. 10299), an but one juvenile shells. 

Locality and horizon. Mandawa-Lonji creek traverse, Mandawa area, Tangan- 
yika ; Lower Kimmeridgian. 

Remarks. This species has the same general aspect as various representatives of 
Paracerithium from the Jurassic of France figured by Cossmann (19136, pi. 13, figs. 
28-63), but differs from all of them in details of ornament. 



160 JURASSIC BIVALVIA AND GASTROPODA 

Genus CRYPT A ULAX Tate 1869 



Cryptaulax bussagensis (Cossmann) 
PL 27, figs. la, b 



1843 
1851 
1863 
1885 
1899 



Cerithium pentagonum d'Archiac : 384, pi. 31, fig. 6 (non Bronn, 1831). 
Cerithium pentagonum d'Archiac ; Morris & Lycett : 39, pi. 9, fig. 22. 
Cerithium ? negleclum Lycett : 92, pi. 44, fig. 21 (non Deshayes, 1833). 
Cerithium pentagonum d'Archiac ; Cossmann : 103. 
Cerithium bussagense Cossmann : 135. 
19136. Cryptaulax pentagonum (d'Archiac) ; Cossmann : 104, pi. 4, figs. 100-102. 

Material. One specimen (no. GG. 10464). 

Locality and horizon. 2 miles W. of Tengeni (village on Pangani river), in 
Mbuzi Mkubwa stream, Tanganyika ; Bathonian (?). 

Remarks. This specimen, a small cerithiiform shell lacking its apical whorls 
but originally about 16 mm. high, has flat whorls bearing five rounded transverse 
costae with intervals of about the same width. The costae are in almost uninterrup- 
ted alignment on successive whorls and are very slightly prosocline. The specimen 
agrees well with examples of the species from the Great Oolite of England. As 
Bronn's Cerithium pentagonum cannot be dismissed as a nomen nudum it is necessary 
to find a replacement for the same name proposed by d'Archiac for the Bathonian 
species. The name Cerithium bussagense was proposed by Cossmann as a substitute 
name for the similarly homonymous C. neglectum Lycett, founded on a specimen 
consisting merely of the earlier whorls of d'Archiac's C. pentagonum, and it is now 
adopted for this species. 

Superfamily STROMBACEA 

Family APORRHAIDAE Philippi 1853 

Genus PIETTEIA Cossmann 1904 

Pietteia stockleyi sp. nov. 

PL 27, figs, ja, b, 8a, b, 14a, b, c 

Specific name. After Mr. G. M. Stockley, formerly Director of the Geological 
Survey of Tanganyika. 

Diagnosis. Shell small (height of holotype, a specimen defective anteriorly, 
7-9 mm.), rather slender, mean spire angle about 20 °. Protoconch elevated, rather 
mammilliform, of two smooth whorls. Later whorls about 5|, rather high in pro- 
portion to their diameter, with a moderately wide sutural ramp which forms an angle 
of about 45 with the axis of the shell and an almost flat outer face, which is vertical 
or even inclined inward abapically on the last whorl, and is separated from the feebly 
excavated, well extended neck of the shell by an obtuse angulation. Dominant 
ornament consisting of spiral threads ; three principal threads, with a secondary 
thread varying in strength intercalated in each interval on the later whorls, are 
present both on the outer face and on the ramp, and further threads, irregularly 



FROM TANGANYIKA AND KENYA 161 

spaced but alternating in strength more or less regularly, ornament the neck. In 
addition, weak collabral ribs, most prominent at the ramp angle, are present except 
on the last whorl, the number on the penultimate whorl being 10. On the last 
whorl the ramp angle bears a short spine half a volution back from the outer lip. 
Aperture narrow, not preserved intact in the available specimens. Outer lip thick- 
ened, with a single short digitation at the position of the ramp angle. 

Holotype and paratypes. Holotype, no. GG.10359. Four paratypes, including 
nos. GG. 10300-01. All ex B.P. Coll. 

Localities and horizon. Near site of Mandawa well no. i, Tanganyika (holo- 
type). Mandawa well no. 6, from depths 46-48 feet, 58-60 feet and 60-62 feet. All 
Bajocian (?). 

Remarks. Although the outer lip is imperfect even in the best-preserved speci- 
men, there is little doubt that this species is a Pietteia related to P. hamus (Eudes- 
Deslongchamps) (see Hudleston, 1888 : 113, pi. 4, figs, ba-d ; pi. 7, fig. 9) and P. 
unicarinata (Hudleston) (1888 : 118, pi. 4, figs, i^a-c), both of which occur in the 
Bajocian of England. It differs from these forms in details of ornament, and in P. 
unicarinata the ramp angle bears two spines on the last whorl, respectively at one- 
quarter and one-half of a volution back from the aperture. 

Pietteia mandawaensis sp. nov. 
PI. 30, figs. 8a, b 

Diagnosis. Shell small (height of holotype, a specimen defective anteriorly, 8.0 
mm.), spire slightly cyrtoconoid, its mean angle probably about 30 ° originally (but 
affected by slight crushing in the available specimens). Protoconch bluntly conical, 
of z\ smooth whorls. Later whorls about 6, of moderate height, the last three with a 
fairly wide sutural ramp which forms an angle of about 45 ° with the axis of the shell, 
and an almost flat outer face which is inclined inward abapically and on the last 
whorl is separated from the feebly excavated neck of the shell by a well-marked, 
obtuse angulation. Ornament consisting of spiral threads crossed by rounded 
collabral ribs which are well marked on the earlier whorls but become obsolete on the 
penultimate and last. Three spiral threads of primary strength are present on both 
the outer face and the ramp, secondary threads of varying strength occupying their 
intervals, and further threads ornament the neck. The number of collabral ribs on 
the pre-penultimate whorl is about 12. On the last whorl a short spine is situated at 
the ramp angle half a volution back from the outer lip. Aperture not preserved 
intact. 

Holotype and paratypes. Holotype, no. GG. 10382. Three paratypes, nos. 
GG.10383-85. 

Locality and horizon. Near site of Mandawa well no. 1 ; Bajocian (?). 

Remarks. This species resembles P. stockleyi, described above, in size and in the 
nature of its ornament, but its whorls, including those of the protoconch, are much 
lower in proportion to their diameter than in that species, and its collabral ribs are 



162 JURASSIC BIVALVIA AND GASTROPODA 

stronger and more numerous. In all four specimens crushing has increased the 
apparent angle of the spire when one of the flattened sides of the shell is viewed, but 
deformation of this nature does not seem to be entirely responsible for the consider- 
able difference in the height of the whorls. 

Pietteia dusseensis sp. nov. 
PI. 27, figs. 16a, b, c 

Diagnosis. Shell rather small (height of holotype c. 13 mm.), spire moderately 
broad, its angle about 25 °. Protoconch unknown. Preserved whorls with a 
flattened, vertical outer face separated by a rounded-off angulation from a broad 
sutural ramp which forms an angle of about 45 ° with the axis of the shell. Orna- 
ment, except on later part of last whorl, consisting of rounded collabral ribs and of 
fine spiral threads overriding them ; the ribs, which are most prominent at the ramp 
angle, where some swell out to form tubercles, are separated by intervals about three 
times as wide ; the number on the penultimate whorl is about 12. The terminal 
rib is particularly prominent, constituting a varix. Later formed part of last whorl 
without ribs, but with a single prominent tuberculate carina at the ramp angle, 
which forms the periphery ; base convex just below periphery, but well excavated 
at the beginning of the neck of the shell ; spiral threads, separated by broader 
intervals, are present on the ramp of the last whorl and on the base. Aperture 
and rostrum not preserved ; the cross-section of the proximal part of a single 
broken-off labral digitation is seen in the holotype. 

Holotype. No. G. 76405. The only specimen. 

Locality and horizon. Dusse, i\ miles S.E. of Rahmu, N.E. Kenya ; Upper 
Oxfordian, Seir Limestones. 

Remarks. This species is referred to Pietteia on account of the nature of its 
ornament and of the evidence that a single stout labral digitation was present. No 
closely comparable Upper Jurassic species can be cited. The French Bajocian 
species Pietteia rarispina (Schlumberger) (Piette 1867 : 100, pi. 20, figs. 1-3) is more 
slender and lacks tubercles on the peripheral carina of its last whorl. Such tubercles 
are found on its contemporary species P. lotharingica (Schlumberger) (Piette 1867 : 
105, pi. 21, figs. 1-11), which, however, is a much more slender shell. 

Genus HARPAGODES Gill 1869 

Harpagodes aff. oceani (Brongniart) 
PI. 28, fig. 3 

1821. Aff. Strombus Oceani Brongniart : 554, 570, pi. 7, fig. 2. 

18676. Aff. Pterocera Oceani (Brongniart) ; de Loriol : 40, pi. 4, figs. 4, 5. 

1 891. Aff. Harpagodes Oceani (Brongniart) ; Piette : 456, pi. 45, figs. 1, 2 ; pi. 48, fig. 1 ; 

pi. 65, figs. 5—7 ; pi. 80, fig. 1 ; pi. 8i, figs. 1-3. 
1910. Aff. Strombus Oceani Brongniart ; Lemoine, pi. 176. 

Material. Four specimens (nos. GG. 10319-22). 



FROM TANGANYIKA AND KENYA 163 

Localities and horizon. Along Mbaru stream, 1 mile N.W. of Mbinga, Tangan- 
yika. Also along Manyuli stream, just W. of Nautope and f mile N.W. of Nautope, 
Tanganyika. Callovian. 

Remarks. The best preserved specimen retains the expanded outer lip, on which 
are four fairly evenly spaced rounded ribs which terminated in labral digitations 
(now broken off). No doubt a further digitation, also no longer preserved, adhered 
to the spire. Rounded spiral cords of secondary strength occupy the intervals 
between the main ribs, three being visible in the least eroded interval. This speci- 
men agrees very well with some of the above-cited figures of the typical H. oceani, 
for example, Piette's pi. 45, fig. 1, and differs from any of that author's figures of 
other species of Harpagodes. It is, of course, possible that, if perfectly preserved 
specimens were available, the form now recorded would prove to differ from Brong- 
niart's species in the details of its labral digitations. H. oceani occurs typically in 
Europe in the Upper Kimmeridgian (Portlandian of French authors) and is not 
known from any horizon as low as Oxfordian, the latest possible age of the East 
African specimens. 



Harpagodes thirriae (Contejean) 
PI. 28, figs. 1, 2 

i860. Pterocera carinata Contejean : 243 (non Roemer sp.). 

i860. Pterocera Thirriae Contejean : pi. 9, figs, i, 2. 

1861. Pterocera Thirriai (sic) Ctj. ; Thurmann & Etallon : 133, pi. 12, fig. 109. 

1861. Pterocera Oceani Delab. ; Thurmann & Etallon : 133, pi. 12, fig. no. 

1891. Harpagodes Thirriae (Contej.) ; Piette : 452, pi. 55, figs. 2, 3 ; pi. 59, figs. 1, 2 ; pi. 68, 

figs. 2-5 ; pi. 71, figs. 1, 2. 

1897. Harpagodes cf. Thirriae (Contej.) ; Futterer : 615. 

i960. Harpagodes oceani (Brongniart) ; Joubert, pi. 12, figs. j,a-c. 

Material. Several specimens. 

Localities and horizons. io| miles S.W. of Raiya hills ; N. of Figfirya, 
northern Raiya hills ; 1 mile S.W. of Melka Dakacha ; 3 miles N.E. of Melka Daka- 
cha ; all N.E. Kenya ; Upper Kimmeridgian, Dakacha Limestones. 

Remarks. This species is easily recognized by the broad, strongly projecting keel 
which is present on the middle of the later part of the last whorl. In addition, two 
faint spiral ribs are visible below this keel on the internal moulds of which the material 
studied consists. There are, however, no ribs above the keel corresponding to more 
posteriorly situated digitations, three of which (including the one adhering to the 
spire) are shown in Piette's pi. 71. In Europe this species has been recorded only 
from the Kimmeridgian. 



164 JURASSIC BIVALVIA AND GASTROPODA 

Superfamily NATICACEA 

Family AMPULLOSPIRIDAE Cox 1930 

Genus AMPULLOSPIRA Harris 1897 

Ampullospira besairiei sp. nov. 
PL 28, figs. 10, 11a, b, 12a, b, 13 

Specific name. After Dr. H. Besairie, collector of specimens of this species from 
Madagascar. 

Diagnosis. Shell attaining a moderately large size for the genus (height of largest 
specimen, from Madagascar, 52 mm.), height well in excess of diameter in undis- 
torted specimens ; height of aperture equal to or slightly exceeding one-half of that 
of shell. Apex acute, early whorls strongly and evenly convex, later whorls develop- 
ing a broad, almost horizontal, slightly concave sutural shelf, separated by a rounded- 
off angulation from the moderately convex outer face of the whorl. Last whorl 
globose, very broadly convex at the periphery, which lies approximately along the 
prolongation of the last suture, and with the evenly convex curve of its outline 
continuous as far as the aperture in most specimens ; in some specimens, however, 
the outline is even slightly concave near the aperture. Umbilical opening a narrow 
cleft in some specimens, umbilicus perhaps absent in others. Aperture higher than 
broad. Columellar lip concave, or else almost straight and leaning slightly to the 
left, and forming an obtuse angle or merging in a broad curve with the parietal lip ; 
margin of columellar lip narrowly reflected, with a slightly detached margin, partly 
covering the umbilical cleft, and continued across the parietal region to the top of 
the outer lip by the margin of a narrow but moderately thickened inductura. Outer 
lip imperfect in all available specimens ; growth-lines only slightly prosocline. 

Holotype and paratypes. Holotype, no. GG.10304, ex B.P. Coll. Several 
paratypes, including nos. GG.10305, G.65864-68, 65884-95. 

Localities and horizon. Lihimaliao creek, at a point near Mbaru creek, 
Mandawa area, Tanganyika (type-locality) ; near site of Mandawa well no. 1, 
Tanganyika (young specimen) ; Mont Bory, Maevatanana district, N.W. Madagas- 
car ; S.W. of geodetic point Antery, Maevatanana district, N.W. Madagascar. All 
probably Bajocian. 

Remarks. This species much resembles Ampullospira sharpei (Morris & Lycett) 
(1851 : 46, pi. 11, fig. 22) from the Bathonian of England, but in that species the 
spire is higher than in the form now described, the sutural shelf slopes slightly, is not 
concave, and is present at an earlier stage of growth, and the last whorl is more 
angular in outline. In the type species of Ampullospira, A. canaliculata (Morris & 
Lycett) (1851 : 45, pi. 11, figs. 23, 23a), from the Bajocian and Bathonian of England, 
the sutural shelf is narrower and the margin of the columellar lip scarcely reflected. 



FROM TANGANYIKA AND KENYA 165 

Ampullospira dejanira (d'Orbigny) 
PL 28, fig. 8 

1852. Natica Dejanira d'Orbigny : 209, pi. 296, figs. 1, 2. 

i960. Ampullospira eudora (d'Orbigny) ; Joubert, pi. 12, figs. \a, b (non d'Orbigny sp.) 

Material. Several specimens (nos. G.76392-96, G.76398, G.76406-08). 

Localities and horizon. Wilderri hill, n miles S.S.W. of Rahmu, N.E. Kenya ; 
low hills at Dusse, ij miles S.E. of Rahmu, N.E. Kenya. Upper Oxfordian, Seir 
Limestones. 

Remarks. The specimens included in this species are characterized by their 
elevated spire, which occupies from rather more than one-third to about one-half of 
the total height of the shell, by their highly and evenly convex whorls, and by the 
considerable breadth of the last whorl, the maximum diameter of which much ex- 
ceeds the height of the aperture and is approximately equal to the total height of the 
last whorl. An umbilicus appears to be absent. The largest specimen, when com- 
plete, was about 55 mm. high and the diameter of its last whorl was about 44 mm. 
When first recorded, these specimens were referred to the species Ampullospira 
eudora (d'Orbigny) (1852 : 211, pi. 297, figs. 1-3), which has an equally elevated 
spire, but they differ from that species in their relatively broader and more strongly 
convex last whorl, and agree more closely with d'Orbigny 's figures of A. dejanira, a 
species which he records from a number of French Upper Oxfordian localities. 



Ampullospira quennelli sp. nov. 
PL 29, figs. 2a, b, c, 3a, b, c 

Specific name. After Mr. A. M. Quennell, formerly Director of the Tanganyika 
Geological Survey, collector of the holotype. 

Diagnosis. Shell of medium size for the genus (height of holotype 34 mm.), 
globose, height exceeding diameter. Spire slightly obtuse, its height rather less than 
one-third of that of shell ; spire whorls with moderately convex outer face, separated 
by a sharp angulation from a flat or slightly concave sutural ledge which is of moder- 
ate width on last whorl. Last whorl broadly convex at periphery and with an evenly 
convex basal outline. Umbilicus apparently absent. Growth-lines slightly prosocline. 
Breadth of aperture about two-thirds of its height. Details of inner lip uncertain 
(owing to obscuring matrix). 

Holotype and paratypes. Nos. G. 91998, GG. 10324-26 respectively. There 
are, in addition, several internal moulds, mostly deformed by pressure, which 
probably belong to this species. 

Localities and horizons. Nchia stream, 2 miles W.N.W. of Mandawa, Tangan- 
yika ; Lonji stream, E.N.E. of Nandenga, Tanganyika ; both Callovian. Im- 
perfect specimens from about the same horizon and probably referable to this species 
are from the Lonji stream, E.N.E. of Mandenga, from the Lihimaliao stream, at a 
point I mile E. of Njenga, and from the Mbaru stream, at a point 1 mile N.W. of 



[66 JIRASSIC BIVALVIA AND GASTROPODA 

Mbinga. Just W. of Mabokweni, 4 miles N.W. of Tanga, Tanganyika (type-locality) ; 
Kimmeridgian. 

Remarks. The specimens now recorded come from two rather widely separated 
horizons (Callovian and Kimmeridgian), but the material available does not justify 
their reference to more than one species. The sutural ledge is a little broader in the 
Kimmeridgian specimen serving as holotype than in the Callovian specimens, but 
the difference is no greater than is commonly found in specimens of the same species 
of Ampullospira. 

The sutural ledge suggests comparison with several forms found in the Bathonian 
of Europe, for example, A. gradifera (Piette) (Cossmann 1885 : 138, pi. 16, figs. 15, 
16), but its lower spire distinguishes the present species from any of these forms. In 
A. crithea (d'Orbigny) (1852 : 200, pi. 292, figs. 5, 6), Lower Oxfordian of France, the 
shell is less globose and the sutural ledge narrower and more excavated. 

A species of the genus Globularia, " Natica " pelops d'Orbigny (1852 : 188, pi. 288, 
figs. 16, 17), from the Upper Lias of France, may be mentioned particularly as 
closely resembling the present form in the general shape of the shell and in size, but 
it lacks a sutural ledge. 

Genus GLOBULARIA Swainson 1840 

Globularia hemisphaerica (Roemer) 
PL 28, fig. 9 

1836. Nerita hemisphaerica Roemer : 156, pi. 10, figs, ya, b. 

1852. Natica hemisphaerica d'Orb. ; d'Orbigny : 204, pi. 294, rigs, i, 2. 

1861. Natica hemisphaerica d'Orb. ; Thurmann & Etallon : 118, pi. 10, fig. 75. 

1868. Natica hemispherica (Roemer) ; de Loriol : 43, pi. 3, figs. 3, 4. 

1872. Natica hemispherica (Roemer) ; de Loriol : 118, pi. 8, figs. 4-6. 

1881. Natica hemispherica (Roemer) ; de Loriol : 33, pi. 8, fig. 7. 

1887. Natica hemisphaerica (Roemer) ; de Loriol : 152, pi. 16, fig. 7. 

1905. Natica cf. amata d'Orb. ; Krumbeck : 127, pi. 13, figs, ga, b. 

1909. Natica hemisphaerica (Roemer) ; Brosamlen : 269, pi. 20, fig. 36. 

i960. Globularia hemisphaerica (Roemer) ; Joubert, pi. 12, figs. 4a, b. 

Material. Four specimens (nos. G. 76374, G. 76384-86). 

Localities and horizon. Melka Dakacha, N.E. Kenya, and 3 miles to the N.E. ; 
also N. of Figfirya, northern Raiya hills, N.E. Kenya. All Upper Kimmeridgian, 
Dakacha Limestones. 

Remarks. This species, with its very low, obtusely rounded spire, its large last 
whorl, and its wide, obliquely extended aperture, is easily recognized. In Europe 
its range extends throughout the Kimmeridgian and probably into the Portlandian. 

Globularia phasianelloides (d'Orbigny) 
PL 29, figs, ia, b 

1852. Natica phasianelloides d'Orbigny : 212, pi. 297, fig. 6. 

1872. Natica phasianelloides d'Orbigny ; de Loriol : 115, pi. 7, figs. 19, 19a. 



FROM TANGANYIKA AND KENYA 167 

1874. Natica phasianelloides d'Orbigny ; de Loriol : 349, pi. 8, fig. 24. 
i960. Globularia phasianelloides (d'Orbigny) ; Joubert, pi. 12, fig. 5. 

Material. Two specimens (nos. G. 76378, G. 76397). 

Localities and horizons. Low hills at Dusse, ij miles S.E. of Rahmu, N.E. 
Kenya ; Upper Oxfordian, Seir Limestones. 2 miles S. of Melka Dakacha, N.E. 
Kenya ; Upper Kimmeridgian, Dakacha Limestones. 

Remarks. This species is characterized by its elevated spire, which occupies 
about one-third of the total height of the shell, by the feeble convexity of its whorls, 
and by its relatively narrow last whorl, the maximum diameter of which is about 
equal to the height of the aperture. The larger of the two specimens is about 44 mm. 
high, with a diameter of 31 mm. The African specimens agree well with published 
figures of specimens of the species from Europe, particularly those of de Loriol (1872). 
In Europe the species occurs in the Lower Kimmeridgian. 

Globularia hennigi sp. nov. 
PI. 28, figs. 5a, b, c 

Specific name. After E. Hennig, an early worker on the Jurassic geology of 
Tanganyika. 

Diagnosis. Shell of small-medium size (height of holotype 16 -6 mm.), globose. 
Spire low, occupying about one-third of the height of the shell, coeloconoid, with the 
apex very acute. Whorls strongly and evenly convex ; last whorl strongly convex 
at periphery, and with an evenly convex basal outline ; maximum diameter of last 
whorl slightly less than height of shell. No umbilicus. Growth-lines moderately 
prosocline. (The aperture is not preserved intact.) 

Holotype. No. G. 76391. The only specimen. 

Locality and horizon. 2 miles S. of Melka Dakacha, N.E. Kenya ; Upper Kim- 
meridgian, Dakacha Limestones. 

Remarks. This species closely resembles Natica crassitesta Dietrich (1914 : 124, 
pi. 11, figs. 18a, b), from the Neocomian of Tendaguru, but has a slightly less elevated 
spire. Natica venelia de Loriol (1874 : 341, pi. 8, figs. 9-12), from the Portlandian 
of Boulogne, France, has a slightly higher spire and strongly pronounced growth- 
rugae. The French Bathonian form Natica lanceolata Piette, transferred to Ampul- 
Una and figured by Cossmann (1885 : 137, pi. 3, fig. 24 ; pi. 16, fig. 32), also has a 
higher spire. 

Family NATICIDAE Gray 1834 

Genus PICT AVI A Cossmann 1925 

Pictavia tanganyicensis sp. nov. 

PI. 28, figs. 6a, b, c, ya, b 

Diagnosis. Shell small (height of largest specimen, when complete, c. 8 mm.), 
ovate-conical, diameter about two-thirds of height, aperture occupying slightly less 



168 JURASSIC BIVALVIA AND GASTROPODA 

than one-half of total height. Protoconch conical, with minute apex. Spire acute, 
conical, consisting of feebly to moderately convex, smooth whorls, abutting simply 
at the sutures. Last whorl evenly and strongly convex at periphery, its outline 
flattening out basally but not becoming definitely concave before reaching the aper- 
ture. No distinct umbilicus. Aperture pyriform, peristome not continuous across 
parietal region. Columellar lip thin, rather extended, straight or almost so, vertical 
or leaning slightly to the left, and joining the basal margin in an even curve. Outer 
lip defective or crushed in the available specimens, apparently almost orthocline, 
although growth-lines are scarcely distinguishable on the surface of the shell. 

Holotype and paratypes. Holotype, no. GG.10302 ; several paratypes, in- 
cluding no. GG. 10303. Ex B.P. Coll. 

Locality and horizon. Near site of Mandawa well no. i, Tanganyika ; Bajo- 
cian (?). 

Remarks. This species resembles the type-species of Pictavia, Natica pictaviensis 
d'Orbigny (1852 : 191, pi. 289, figs. 8-10), from the Bajocian of France, in the general 
morphology of the shell, but its small size distinguishes it both from that species and 
from other Middle Jurassic representatives of the genus that have been described 
previously. 

(Superfamily uncertain) 

Family MATHILDIIDAE 

Genus PROMATHILDIA Andreae 1887 

Promathildia aff. opalini (Quenstedt) 
PL 29, figs. 6a, b 



1832 
1856 
1882 
1883 
1884 
1891 
1891 
1909 



Aff. Turritella elongata Zieten : 43, pi. 32, fig. 5 (non J. Sowerby, 1814). 

Aff. Turritella opalina Quenstedt : 326, pi. 44, fig. 15 (non Adams & Reeve 1850). 

Aff. Turritella opalini Quenstedt : 300, pi. 196, figs. 20, 21. 

Aff. Cerithium torulosi Quenstedt, pi. 205, fig. 53. 

Aff. Turritella (Mathilda) opalina Quenstedt var. canina Hudleston : 200, pi. 7, fig. 9. 

Aff. Turritella (Mathilda) opalina Quenstedt ; Hudleston : 231, pi. 17, figs. 3a, b. 

Aff. Turritella (Mathilda) opalina var. canina Hudleston ; Hudleston : 232, pi. 17, fig. 4. 

Aff. Turritella opalina Quenstedt : Brosamlen : 275, pi. 20, fig. 44 ; pi. 21, fig. 1. 



Material. One specimen (no. GG. 10270). 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. The specimen, which is 13-5 mm. high, lacks the actual apex, but 
consists of about 6| early whorls of an acute, turriculate shell. The whorls, which 
are strongly and evenly convex, are mostly eroded, but the last one can be seen to be 
ornamented with about 8 obscurely granose spiral cords. 

Hudleston (1891 : 231) suggested that Quenstedt's name Turritella opalina might 
" be accepted as a generalized term for elongate Turritellae of Jurassic age possessed 
of about six or seven spirals ", and mentioned that the spirals were slightly granula- 



FROM TANGANYIKA AND KENYA 169 

ted. His " var. canina " from the Dogger (? Upper Lias, Yeovilian) of Blea Wyke, 
Yorks, has eight spirals and much resembles the small shell now recorded. In 
Germany Quenstedt's species is particularly characteristic of the " Brown Jura a" 
but ranges up into the " Brown Jura fi " (both Aalenian), and, according to Brosam- 
len, most specimens have six spirals. The age of the specimen now recorded (Toar- 
cian) is slightly earlier than that of any recorded European occurrence of the species. 
The specific name opdlina, under which Quenstedt described this form in 1856, was 
a homonym, but his emended name opalini, published in 1882, may be adopted. 

Subclass OPISTHOBRANCHIA Milne Edwards 

Order ENTOMOTAENIATA Cossmann 

Superfamily NERINEACEA 

Family NERINEIDAE Zittel 1873 

Genus COSSMANNEA Pchelintsev 1927 

Cossmannea hennigi (Dietrich) 
PI. 30, fig. 7 
1904. Nerinea Hennigi Dietrich : 134, pi. 12, fig. 6, pi. 13, figs. ^a-c. 

Material. Two specimens (nos. G. 48914, G. 48917). 

Localities and horizon. Bed of Maimbwi river, and along upper part of 
tributary to same river, near Tendaguru, Tanganyika ; Upper Kimmeridgian, 
" Trigonia smeei " Bed and slightly below it. 

Remarks. The generic name Cossmannea is applicable to the group of species 
designated as Nerinea s.str. by some previous writers, who ignored the fact that the 
type-species of Nerinea should properly be taken as N. mosae Deshayes. This group 
is characterized by concave whorls, a bulging sutural region, the presence of 2-3 
internal folds, and the usually relatively large size of the shell. 

In C. hennigi the concavity of the whorls is only moderate and no tubercles are 
present on them. There are three strong internal folds. There is a close external 
resemblance to Cossmannea desvoidyi (d'Orbigny) (Cossmann 1898 : 56, pi. 5, figs. 14, 
21) which ranges from the Upper Oxfordian to the Tithonian in Europe. C. desvoidyi 
however, has only two internal folds and is slightly more slender. The maximum 
diameter of the largest specimens of C. hennigi now recorded is 29 mm. 

Genus NERINELLA Sharpe 1850 
Nerinella }rnuelleri Cox 

1900. INerinea Credneri Miiller : 537, pi. 17, figs. 11-13 (non Alth 1873, nee Zittel 1873). 
1954. ?Nerinella muelleri Cox : 16. 

Material. One specimen (no. GG. 10339). 



i 7 o JURASSIC BIVALVIA AND GASTROPODA 

Locality and horizon. Along Lihimaliao stream at a point about f mile E. of 
Xjenja, Tanganyika ; Upper Oxfordian(P). 

Remarks. The type-specimens of this species came from the locality " 1-5 km. 
W. of the Mahokondo stream, 24-5 km. N.W. of Kiswere ", where the beds are now 
known to be Callovian in age. The single ill-preserved fragment of a Nerinella now 
recorded appears to belong to N. maelleri, but it does not allow Muller's published 
description, referred to below in the description of N. cutleri, to be amplified. 



Nerinella cutleri sp. nov. 
PI. 30, figs. 4«, b 

1914. Nerinella Credneri (Muller) ; Dietrich : 142, pi. 12, fig. 8 (non Nerinea credneri Muller 
1900 (non Zittel), = Nerinella muelleri Cox). 

Specific name. After the late W. E. Cutler, the first leader of the British Museum 
East African Expedition. 

Diagnosis. Shell very slender, up to about 13 cm. in length ; whorls feebly 
concave to almost flat, their height approximately equal to their diameter ; earlier 
whorls ornamented with very obscurely granose spiral threads, the number of which 
increases to about nine at a diameter of about 5 mm. ; later whorls almost smooth. 
One prominent fold low on the columella ; one prominent parietal fold occupying 
the angle between the columella and the upper wall of the whorl ; one broad-based 
fold, which usually is more or less quadrate in cross-section with two well-marked 
inner angles, but is not definitely bifid, just below the middle of the outer wall ; and 
(in some specimens only) a very weak fold on the basal wall. 

Holotype and paratypes. Holotype, no. G. 46026, a broken specimen selected 
because it retains its surface ornament. Numerous paratypes, the majority eroded. 

Localities and horizon. Several localities in Tendaguru neighbourhood (Ki- 
pande path (type-locality), N. of Kipande, 1 mile N.W. of Tendaguru hill, scarp at 
Kindope, Namapuya creek) and Kinjele, 5 miles W. of Mtapaia, N. of Tendaguru ; 
Upper Kimmeridgian, Nerinella Bed. Lilomba creek and f mile S. of Nautope, near 
Tendaguru ; Upper Kimmeridgian, " Trigonia smeei " Bed. Hillside 3 miles E. of 
Rahmu, south of the road to Mandera, N.E. Kenya ; Upper Oxfordian, Seir Lime- 
stones. 

Remarks. The common Tendaguru Nerinella has hitherto been identified as N. 
credneri (Muller), a species more correctly known as N. muelleri Cox and recorded 
above. This latter species has been accepted as a long-ranging one both by Dietrich 
(1914 : 142) and by Hennig (1924 : 51), but this conclusion seems to need critical re- 
examination. For interpretation of N. muelleri I have to rely mainly on Muller's 
description and figures. Externally, this species is very close to the Tendaguru 
form both as regards whorl outline and ornament, the nodose threads which are 
present on the earlier whorls disappearing at a later growth-stage, leaving the surface 



FROM TANGANYIKA AND KENYA 171 

almost smooth. Muller's fig. 12 indicates that the spiral threads ornamenting the 
whorls of N. mnelleri bear more conspicuous granules than have been observed in 
Tendaguru specimens, but the granules may have been exaggerated by the artist. 
A more noticeable difference lies in the shape of the labral fold, which Muller's fig. 13 
shows to be relatively slender where it joins the outer lip and to split up distally into 
two branches of appreciable length. In Tendaguru specimens the corresponding 
fold is broad at its base and its outline is either triangular or square, at times with 
slightly projecting angles. This difference, considered in conjunction with the much 
higher stratigraphical horizon, seems to justify the recognition of the Tendaguru 
Nerinella as a species distinct from N. muelleri. Of European species, N. damisensis 
(d'Orbigny) (1852 : 118, pi. 267, figs. 4-6) has a labral fold rather similar in cross- 
section to that of the Tendaguru species, but its whorls are more strongly concave 
and more coarsely ornamented. 

The specimens from the Seir Limestones of N.E. Kenya consist of partly weathered- 
out shells on the surface of a bed of hard limestone. Their surface features are not 
preserved, but erosion has exposed the internal structure of some of the shells, which 
include specimens with folds agreeing well with those of N. cutleri, particularly as 
regards the shape of the one on the outer lip. Other genera are also represented. 



Nerinella mandawaensis sp. now 

PL 30, figs. 1, 2a, b, 3 

Diagnosis. Shell very slender, the largest specimens having a maximum dia- 
meter of 6-5 mm. and an estimated length, when complete, of about 10 cm. Whorls 
moderately concave, with the sutural region forming a swollen band ; height of 
whorls slightly exceeding their diameter. Ornament consisting of granose spiral 
threads ; some specimens with four primary ones throughout, with weak interstitials, 
other specimens with up to eight threads on later whorls, where they differ very little 
in strength but are distributed irregularly. One not very prominent internal fold 
on the lower part of the columella ; one narrow, thorn-like parietal fold occupying 
the angle between the columella and the upper wall of the whorl ; and one prominent 
but only moderately broad fold, widening slightly at its distal end in some specimens, 
just below the middle of the outer wall. 

Holotype and paratypes. Nos. GG.10333, GG.10334-38 respectively, the para- 
types in pieces of sandstone some containing several specimens. 

Locality and horizon. Along Mandawa-Namakongoro stream, about i mile 
W. of Mandawa, Tanganyika ; Middle-Upper Kimmeridgian. 

Remarks. The specimens are of the same age as Nerinella cutleri, from Tenda- 
guru, but their recognition as a distinct species is justified by their more strongly 
concave whorls and by the differences in their internal folds. The labral fold, in 
particular, is narrower but more prominent than that of the Tendaguru form. 



\7i JURASSIC BIVALVIA AND GASTROPODA 

Genus PSEUDONERINEA de Loriol 1890 

Pseudonerinea clio (d'Orbigny) 
PI. 30, figs. 5, 6 

18506. Chemnitzia Clio d'Orbigny : 2. 

1851. Chemnitzia Clio d'Orbigny : 66, pi. 249, figs. 2, 3. 

1 861. Chemnitzia Clio d'Orb. ; Thurmann & Etallon : 87, pi. 6, fig. 26. 

1867a. Pseudomelania Clio (d'Orbigny) ; de Loriol : 14, pi. B, fig. 1. 

1887. Pseudomelania Clio (d'Orbigny) ; de Loriol : 139, pi. 14, figs. 5, 6. 

1894a. Pseudonerinea Clio (d'Orbigny) ; de Loriol : 42, pi. 3, figs. 5, 6. 

1898. Pseudonerinea Clio (d'Orbigny) ; Cossmann : 10, pi. i, figs. 11, 12, 16. 

191 1. Pseudomelania aff. Clio (d'Orbigny) ; Blaschke : 166, pi. 4, fig. 6. 

Material. Six specimens (including nos. GG. 10329-31), mostly imperfect. 

Locality and horizon. \ mile E. of Nangororo, Tanganyika ; Upper Kim- 
meridgian. 

Remarks. The largest of the specimens now recorded is about 57 mm. high. 
The specimens agree quite well with European ones in the general form of the shell 
and the relative height of the almost flat whorls. In one specimen the anterior out- 
let of the aperture, which undercuts the columella, is well seen, but its canal-like 
appearance is intensified by the fact that the basal lip is broken away. In the fig- 
ures of P. clio published by d'Orbigny and by Thurmann & Etallon the anterior margin 
of the aperture is restored, incorrectly, as entire and evenly rounded. Cossmann 
describes the aperture of P. clio as " largement sinueuse a la base " and the columella 
as " se terminant en pointe un peu inflechie contre la sinuosite anterieure de 
l'ouverture, sans former de bee avec le contour superieur [i.e. the basal margin]. " 
De Loriol (1894a : 42, pi. 3, fig. 5), however, figures a specimen with an anterior out- 
let very much like that of the form now described and comments upon it. Cossmann 
(1898 : 4) would refer species with a canal-like outlet to Fibula rather than to Pseudo- 
nerinea, but in typical species of Fibula the shell is much less slender than in forms 
such as that now recorded. One of the specimens has been sectioned and shown to 
be without internal folds, as in all species of Fibula and Pseudonerinea. In Europe 
this species occurs in coralline beds of the Kimmeridgian stage. 

Genus TROCHALIA Sharpe 1850 

Trochalia depressa (Voltz) 
PI. 29, fig. 7 

1835. Nerinea depressa Voltz : 425. 

1836. .Nerinea depressa Voltz ; Bronn : 549, pi. 6, figs. 17a, b. 

1850. Trochalia depressa (Voltz) ; Sharpe : 107. 

1 85 1. Nerinea depressa Voltz ; d'Orbigny : 104, pi. 259 (as N. umbilicata). 
1861. Nerinea depressa Voltz ; Thurmann & Etallon : 97, pi. 8, fig. 42. 
1869. Cryptoplocus depressus (Voltz) ; Gemmellaro : 42, pi. 6, figs. 9-11. 

1869. Cryptoplocus umbilicatus (d'Orb.) ; Gemmellaro : 43, pi. 2 bis, figs. 18, 19. 
1874. Trochalia depressa (Voltz) ; de Loriol : 312, pi. 7, fig. 2. 
1886. Trochalia depressa (Voltz) ; de Loriol : 115, pi. 11, figs. 10, 11. 

1898. Cryptoplocus depressus (Voltz) ; Cossmann : 158, pi. 11, figs. 33, 34 : pi. 12, figs. 3, 4, 7, 
11, 12. 



FROM TANGANYIKA AND KENYA 173 

Material. Several specimens (nos. G. 70517-18, G. 76375-76, G. 76389) preserved 
in hard limestone. 

Localities and horizon. Melka Dakacha, 1 mile W. of Melka Dakacha, and 1 
mile S.S.W. of Melka Dakacha, N.E. Kenya ; Upper Kimmeridgian, Dakacha Lime- 
stones. 

Remarks. These specimens agree well with European ones in the angle of their 
spire and in their very feebly convex, non-gradate whorls. The largest one was 15 
cm. or more high when complete. Axial sections show the broad umbilicus and a 
single, very strong internal fold, projecting from the upper wall of the whorls. In 
Europe this species ranges from the Lower Kimmeridgian to the Upper Kimmerid- 
gian and probably higher. 



Order TECTIBRANCHA Cuvier 

Superfamily BULLACEA 

Family ACTEONIDAE d'Orbigny 1842 

Genus ACT EO NINA d'Orbigny 1850 

Subgenus STRIACTAEONINA Cossmann 1895 

Acteonina {Striactaeonina) supraliasica sp. nov. 
PI. 29, figs. 4«, b, c 

Diagnosis. Of medium size for the subgenus (height of largest specimen c. 15 
mm.), with a relatively high and narrow, cylindrical last whorl and an acute, gradate- 
conical spire, the height of which is about one-quarter of that of the shell. Whorls 
with a steep, flattened ramp which forms an angle of about 60 ° with the horizontal 
and a subvertical outer face, of which only a narrow strip is exposed on the spire. The 
outline of the last whorl is broadly convex where it merges abapically into the steeply 
sloping base. Outer face and base ornamented with unevenly spaced, linear spiral 
grooves. Aperture very narrow adapically ; outer lip not preserved intact ; inner 
lip simple, with a thin, narrowly spread, distinctly margined coating of callus. 

Holotype and paratypes. Nos. GG.10271 and GG.10272-74 respectively, four 
specimens in all. 

Locality and horizon. Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya ; 
Upper Lias, Toarcian, Didimtu Beds. 

Remarks. The specimens are rather eroded and it is not possible to see if the 
spiral groove commonly found just below the ramp in species of Striactaeonina is 
present. The general form of the shell resembles that of some species of Cylindrites, 
but the presence of spiral ornament and the absence of folds low on the columellar lip 
distinguish it from that genus. 



174 JURASSIC BIVALVIA AND GASTROPODA 

Family AKERIDAE Cossmann 1895 

Genus AKERA Muller 1776 

Akera tanganyicensis sp. nov. 
PI. 29, figs. 5a, b 

Diagnosis. Of medium size (height of holotype 27-5 mm.), cylindrical, involute, 
with flattened spire ; maximum diameter about three-fifths of height in holotype 
(in which specimen, however, it is probably increased a little by crushing). Sutures 
impressed. Sides of last whorl very feebly convex and diverging slightly in an 
abapical direction as far as the periphery of the base, which lies at about the lower 
third of the height of the shell, and below which the outline of the base is very feebly 
convex. Aperture of moderate breadth above, where the inner lip is formed by the 
steep face of the previous whorl, broadening below, where the inner lip recedes to the 
columella. Outer lip vertical, curving back to a slight extent at its upper end, to 
meet the suture ; basal margin of aperture forming an even curve ; columellar lip 
vertical, short. 

Holotype. No. GG. 10332. The only specimen. 

Locality and horizon. Along Mbaru stream, 1 mile N.W. of Mbinga, Tangan- 
yika ; Callovian. 

Remarks. This form seems to be congeneric with a series of Jurassic species 
which Cossmann (18966 : 127-131) includes in Acera [better, Akera], a genus origin- 
ally founded on Recent forms. In A. mediojurensis Cossmann (18966 : 128, pi. 6, 
figs. 8, 9), from the Callovian and Lower Oxfordian of France, the side of the last 
whorl is more strongly convex and the shell is slightly broader in proportion to its 
height than in the species now described. In A. truncata (Lennier), from the Kim- 
meridgian of France, the shell, as figured by Cossmann (18966 : 130, pi. 6, figs. 13, 
14), is even closer to the present form in shape, but is slightly more slender. 

v list of fossil localities, with species collected at each 
Localities in S.E. Tanganyika 

Tendaguru : Tingutitinguti creek, S.W. of Tendaguru hill ; Upper Kimmeridgian, 
" Trigonia smeei " Bed. 

Cucullaea sp., Modiolus bipartitus (J. Sowerby), Mytilus (Falcimytilus) dietrichi 
sp. nov., Lithophaga suboblonga Dietrich, Gervillella aviculoides (J. Sowerby), 
M eleagrinella radiata (Trautschold), Lima, (Plagiostoma) sp., Lima (Acesta) 
cutleri sp. nov., Liostrea dubiensis (Contejean), Trigonia (Indotrigonia) smeei 
auct., Hippopodium quenstedti (Dietrich), Astarte sp., Opis sp., Lucina sp., 
Mactromya sp., Protocardia schencki Muller, Protocardia {Tendagurium) pro- 
pebanneiana (Dietrich), Eomiodon (Africomiodon) cutleri sp. nov., Symmetro- 
capulus ? sp., Pseudomelania (Oonia) dietrichi sp. nov., Ampullospira ? sp., 
Globularia sp. 



FROM TANGANYIKA AND KENYA 



'75 



Tendaguru : Maimbwi river, S.E. of Tendaguru. Upper Kimmeridgian, " Tri- 
gonia smeei " Bed. 

Meleagrinella radiata (Trautschold) , Trigonia (Indotrigonia) smeei auct., Astarte 
weissermeli Dietrich, Astarte subobovata Dietrich, Cossmannea hennigi (Dietrich). 

Tendaguru : near summit of Tendaguru hill. Upper Kimmeridgian, " Trigonia 
smeei " Bed. 

Meleagrinella radiata (Trautschold). 




Pig. i. Sketch-map of eastern Tanganyika, showing Jurassic outcrops. 



176 JURASSIC BIVALVIA AND GASTROPODA 

Tendaguru : excavation "Mi ", Tendaguru hill. Upper Kimmeridgian, Dino- 
saur Bed. 

Eomiodon dinosaurianum sp. nov. 

Tendaguru : excavation "My". Upper Kimmeridgian, " Trigonia smeei " Bed. 
Mytilus (Falcimytilus) dietrichi sp. nov., Astarte sp. 

Tendaguru : valley N.N.W. of " D " flag, f mile N. of Tendaguru hill, on road to 
Kindope. Upper Kimmeridgian, " Trigonia smeei " Bed. 

Meleagrinella radiata (Trautschold), Trigonia (Indotrigonia) smeei auct., Hippo- 
podium qttenstedti (Dietrich). 

Tendaguru : Dwanika river, N.E. of Tendaguru hill. Upper Kimmeridgian, 
" Trigonia smeei " Bed. 

Trigonia {Indotrigonia) smeei auct., Laevitrigonia dwanikana sp. nov. 

Tendaguru : beyond the N.W. flag, i mile N.W. of Tendaguru hill. Upper Kim- 
meridgian, Nerinella Bed. 

Grammatodon (Indogrammatodon) irritans (Hennig), Cucullaea sp., Gervillella 
aviculoides (J. Sowerby), Stegoconcha gmuelleri (Krenkel), Trigonia migeodi sp. 
nov., Trigonia (Indotrigonia) smeei auct., Hippopodium quenstedti (Dietrich), 
Astarte recki Dietrich, Astarte sowerby ana Holdhaus, Nerinella cutleri sp. nov. 

Tendaguru : 2000 ft. N. of Kipande N. flag, W. of Tendaguru hill. Upper Kim- 
meridgian, Nerinella Bed. 

Stegoconcha gmuelleri (Krenkel), Trigonia (Indotrigonia) smeei auct., Astarte recki 
Dietrich, Astarte sp., A starte sowerby ana Holdhaus, Sphaera subcorrugata Dietrich, 
Homomya hortulana Agassiz, Nerinella cutleri sp. nov. 

Tendaguru : 4th Kipande flag, W. of Tendaguru hill. Upper Kimmeridgian, 
" Trigonia smeei " Bed. 

Cucullaea kipandeensis sp. nov., Grammatodon (Indogrammatodon) irritans 
(Hennig), Astarte recki Dietrich, Eomiodon (Africomiodon) cutleri sp. nov. 

Tendaguru : Kipande creek, W. of Tendaguru hill. Upper Kimmeridgian, 
" Trigonia smeei " Bed. 

Lithophaga suboblonga Dietrich. 

Tendaguru : Kipande path, W. of Tendaguru hill. Upper Kimmeridgian, 
Nerinella Bed. 

Cucullaea kipandeensis sp. nov., Stegoconcha gmuelleri (Krenkel), Chlamys 
(Radulopecten ?) sp., Lissochilus stremmei Dietrich, Nerinella cutleri sp. nov. 



FROM TANGANYIKA AND KENYA 177 

Tendaguru : between first and N. flags, Kipande path, W. of Tendaguru hill. 
Upper Kimmeridgian, " Trigonia smeei " Bed. 

Lopha hennigi (Dietrich), Trigonia {Indotrigonia) smeei auct., " Pleurotomaria " 
sp. 

Tendaguru : 200 yards N.E. of workings at Nguruwe, i| miles S. of Tendaguru 
hill. Upper Kimmeridgian, " Trigonia smeei " Bed. 

Lithophaga suboblonga Dietrich, Trigonia {Indotrigonia) smeei auct. 

Tendaguru : Mtapaia road, N. of Tendaguru. Upper Kimmeridgian, " Trigonia 
smeei " Bed. 

Lopha hennigi (Dietrich), Homomya hortnlana Agassiz. 

Tendaguru : " ditch 2x ", Tapaira trail, S. of Tendaguru. Upper Kimmeridgian, 
" Trigonia smeei " Bed. 

Meleagrinella radiata (Trautschold), Liostrea sp., Astarte sp., Chrysostoma staffi 
Dietrich. 

Tendaguru : road i\ miles N.N.VV. of Tapaira village, S.W. of Tendaguru. 
Upper Kimmeridgian, " Trigonia smeei " Bed. 
Hippopodium quenstedti (Dietrich). 

Tendaguru : 3 miles N.N.W. of Tapaira village, S.W. of Tendaguru. Upper 
Kimmeridgian, " Trigonia smeei " Bed. 

Cucullaea sp., Chlamys sp., Trigonia {Indotrigonia) smeei auct., Sphaera sub- 
corrugata Dietrich. 

Tendaguru : Namapuya creek. Upper Kimmeridgian, Nerinella Bed. 
Nerinella cutleri sp. nov. 

Tendaguru : Nitongola creek. Upper Kimmeridgian, " Trigonia smeei " Bed. 
Meleagrinella radiata (Trautschold), Lima {Plagiostoma) sp., Lima {Acesta) cut- 
leri sp. nov., Trigonia {Indotrigonia) smeei auct., Astarte weissermeli Dietrich, 
Coelastarte dietrichi sp. nov., Protocardia schencki Muller, " Patella " sp. 

Tendaguru : Lilomba creek. Upper Kimmeridgian, " Trigonia smeei " Bed. 
Cucullaea sp., Mytilus {Falcimytilus) dietrichi sp. nov., Lithophaga suboblonga 
Dietrich, Chlamys sp., Chlamys {Radulopecten) kinjeleensis sp. nov., Liostrea sp., 
Trigonia {Indotrigonia) smeei auct., Astarte sp., Lucina cutleri sp. nov., Nerinella 
cutleri sp. nov. 

Kindope, N.N.W. of Tendaguru ; " Kindope river ". Upper Kimmeridgian, 
" Trigonia smeei " Bed. 

Grammatodon {Indogrammatodon) irritans (Hennig), Mytilus {Falcimytilus) 
dietrichi sp. nov., Pinna constantini de Loriol, Meleagrinella radiata (Trautschold), 



178 JURASSIC BIVALVIA AND GASTROPODA 

Entolium corneolum (Young & Bird), Chlamys sp., Lima (Acesta) cutleri sp. nov., 
Lima (Plagiostoma) sp., Liostrea dubiensis (Contejean), Trigonia (Indotrigonia) 
dietrichi Lange, Astarte weissermeli Dietrich, Lucina sp., Protocardia schencki 
Muller, Scurriopsis (Dietrichiella) kindopensis (Dietrich), Lissochilus stremmei 
Dietrich. 

Kindope, N.N.W. of Tendaguru ; about ioo feet down scarp. Upper Kimmerid- 
gian, Nerinella Bed. 

Eonavicula sp. " B ", Modiolus sp., Musculus kindopeensis sp. nov., Pseudolimea 
duplicata (J.de C. Sowerby), Limatula migeodi sp. nov., Protocardia schencki 
Muller. 

Kindope, N.N.W. of Tendaguru ; 30 to 70 feet down scarp. Upper Kimmerid- 
gian, Nerinella Bed. 

Grammatodon {Indogrammatodon) irritans (Hennig), Lithophaga sp., Pinna con- 
stantini de Loriol, Liostrea dubiensis (Contejean), Astarte sp. 

Kindope, N.N.W. of Tendaguru ; bottom of scarp. Upper Kimmeridgian, 
Nerinella Bed. 

Stegoconcha gmuelleri (Krenkel). 

Kindope, N.N.W. of Tendaguru ; three-quarters of way down scarp. Upper 
Kimmeridgian, Nerinella Bed. 

Grammatodon {Indogrammatodon) irritans (Hennig), Apolinter kindopeensis sp. 
nov., Musculus kindopeensis sp. nov., Gervillella aviculoides (J. Sowerby), Pinna 
constantini de Loriol, Trichites sp., Meleagrinella radiata (Trautschold), Entolium 
corneolum (Young & Bird), Chlamys sp., Lima {Acesta) kindopeensis sp. nov., 
Pseudolimea duplicata (J. de. C. Sowerby), Liostrea dubiensis (Contejean), Tri- 
gonia {Indotrigonia) smeei auct., Protocardia schencki Muller, Eomiodon {Africo- 
miodon) cutleri sp. nov., Nerinella cutleri sp. nov. 

Kindope, N.N.W. of Tendaguru ; top of scarp. Upper Kimmeridgian, Nerinella 
Bed. 

Lopha hennigi (Dietrich). 

Kindope, N.N.W. of Tendaguru ; Kindope river, 150 feet below " St." Upper 
Kimmeridgian, Nerinella Bed. 

Grammatodon {Indogrammatodon) irritans (Hennig), Gervillella aviculoides (J. 
Sowerby), Pinna constantini de Loriol, Oxytoma inequivalvis (J. Sowerby), 
Meleagrinella radiata (Trautschold), Bositra somaliensis (Cox), Exogyra nana 
(J. Sowerby), Protocardia schencki Muller, Anisocardia kinjeleensis sp. nov. 

Kindope, N.N.W. of Tendaguru. Upper Kimmeridgian, " Trigonia smeei " Bed. 
Meleagrinella radiata (Trautschold), Placunopsis sp., Trigonia {Indotrigonia) 
smeei auct. 



FROM TANGANYIKA AND KENYA 179 

Kindope, N.N.W. of Tendaguru. Upper Kimmeridgian, Nerinella Bed. 
Lithophaga sp., Lopha? kindopeensis sp, nov. 

Kinjele, 5 miles W. of Mtapaia, N. of Tendaguru. Upper Kimmeridgian, " Tri- 
gonia smeei " Bed. 

Mytilus (Falcimytilus) dietrichi sp. nov., Trigonia (Indotrigonia) smeei auct. 

Kinjele, 5 miles W. of Mtapaia, N. of Tendaguru. Upper Kimmeridgian, Indo- 
grammatodon Bed. 

Grammatodon (Indogrammatodon) irritans (Hennig), Modiolus (Inoperna) per- 
plicatus (Etallon), M eleagrinella radiata (Trautschold) , Entolium corneolum 
(Young & Bird), Liostrea sp., Protocardia schencki Miiller, Anisocardia kinjele- 
ensis sp. nov., Pleitromya uniformis (J. Sowerby). 

N. of Kinjele, 5 miles W. of Mtapaia, N. of Tendaguru. Upper Kimmeridgian, 
" Trigonia smeei " Bed. 

Trigonia (Indotrigonia) smeei auct. 

N. of Kinjele, 5 miles W. of Mtapaia, N. of Tendaguru. Upper Kimmeridgian, 
Nerinella Bed. 

Chlamys (Radulopecten) kinjeleensis sp. nov., Lopha ? kindopeensis sp. nov., 
Nerinella cutler i sp. nov. 

J mile S. of Nautope, 14 miles N.N.W. of Mtapaia. Upper Kimmeridgian, 
" Trigonia smeei " Bed. 

Trigonia (Indotrigonia) smeei auct., Astarte weissermeli Dietrich, Nerinella 
cutleri sp. nov. 

Pindiro well no. 1, depths 162 to 254 feet (B.P.). 9 30' 15" S., 39° 18' 37" E. 
Bajocian (?), Pindiro Shales. 

Corbula pindiroensis sp. nov. 

Mandawa well no. 6, depths 38 to 72 feet (B.P.). 9 25' 4" S., 39 25' 9" E., 
Bajocian (?). 

Gervillella orientalis (Douville), 50-52 feet, Pronoella putealis sp. nov., 46-64 feet, 
Corbula mandawaensis sp. nov., 46-72 feet, Coelostylina mandawaensis sp. nov., 
58-68 feet, Zygopleura mandawaensis sp. nov., 58-66 feet, Procerithium (Rhabdo- 
colpus) mandawaense sp. nov., 38-70 feet, Exelissa africana sp. nov., 50-72 feet, 
Brachytrema sp., 46-54 feet, Pietteia stockleyi sp. nov., 46-62 feet. 

Mandawa well no. 7, depths 92-4520 feet (B.P.). 9 24' 58" S., 39 25' 3" E. 
Bajocian (?). 

Corbula tanganyicensis sp. nov., 3760-4520 feet, Procerithium (Rhabdocolpus) 
mandawaense sp. nov., 92-100 feet. 



180 JURASSIC BIVALVIA AND GASTROPODA 

Lonji creek, W. of Mandawa (B.P. loc. DMM 176). 9 21' 40" S., 39 24' 22" E. 
Callovian (?). 

Grammatodon (Indogrammatodon) virgatus (J. de C. Sowerby), Astarte unilateralis 
J. de C. Sowerby. 

Lonji creek, W. of Mandawa (B.P. loc. DMM 177). 9 21' 47" S., 39 24' 25" E. 
Callovian. 

Thracia viceliacensis d'Orbigny. 

Lonji creek, W. of Mandawa, (B.P. loc. DMM 182). 9 22' 15" S., 39 23' 11" E. 
Upper Kimmeridgian. 
Fimbria sp. " C ". 

Left bank tributary, Lonji creek, W. of Mandawa (B.P. loc. DMM 183). 9 22' 
I 5" S., 39 23' 11" E. Upper Kimmeridgian. 
Astarte lonjiensis sp. nov. 

Lonji creek, W. of Mandawa (B.P. loc. DMM 184). 9 22' 16" S., 39 23' 12" E. 
Upper Kimmeridgian. 

Astarte mandawaensis sp. nov. 

Mandawa-Lonji creek traverse, Mandawa area (B.P. loc. DMM 189). 9 21' 
58" S., 39 25' 36" E. Lower Kimmeridgian. 
Paracerithium lonjiense sp. nov. 

" Station 76 " (about 1^ miles W. of Mandawa), Mandawa-Lonji creek traverse. 
(B.P. loc. DMM 196). 9 22' o" S., 39 25' 20" E. Callovian (?). 
Trigonia elongata J. de C. Sowerby. 

Mandawa-Lonji creek traverse, Mandawa area (B.P. loc. DMM 197). 9 21' 
57" S., 39° 25' 24" E. Upper Oxfordian. 

Eopecten aubryi (Douville), Pholadomya hemicardia Roemer, Pleuromya calcei- 
formis (Phillips). 

Lihimaliao creek, Mandawa area (B.P. loc. DMM 211). 9 25' 13" S., 39 24' 
28" E. Upper Oxfordian. 

Pseudolimea mandawaensis sp. nov., Liostrea polymorpha (Miinster), Astarte 
sowerbyana Holdhaus. 

Lihimaliao creek, near Mbaru creek, Mandawa area (B.P. loc. DMM 214). 9 25' 
30" S., 39 26' E. Bajocian (?), Pindiro Shales. 

Parallelodon pindiroensis sp. nov., Modiolus imbricatus (J. Sowerby), Gervillella 
orientalis (Douville^, Protocardia bipi sp. nov., Protocardia besairiei sp. nov., 
Pronoella pindiroensis sp. nov., Pronoella putealis sp. nov., Ceratomya tanganyi- 
censis sp. nov., Thracia lens (Agassiz), Coelostylina mandawaensis sp. nov., 
Ampullospira besairiei sp. nov. 



FROM TANGANYIKA AND KENYA 181 

Scarp stream on west-facing scarp immediately N. of Matapwa, 20 yards above 
second and bigger waterfall and 550 yards W. of road, Pindiro area (B.P. loc. RS 569). 
9° 39' 2 5" S., 39 24' 34" E. Upper Kimmeridgian. 

Grammatodon (Indogrammatodon) matapwaensis sp. nov., Brachidontes (Arco- 
mytilus) laitmairensis (de Loriol), Chlamys matapwaensis sp. nov., Protocardia 
suprajurensis (Contejean). 

Hillside overlooking Lake Mbuo, Pindiro-Ruwawa valley (B.P. loc. RS. 695). 
9 28' 56" S., 39 19' o" E. Middle Kimmeridgian. 
Entolium corneolum (Young & Bird). 

Mpilepile stream, 800 yards E.N.E. of Mitole road junction, northern Mandawa 
area (B.P. loc. RS 814). 9 16' 13" S., 39 23' 48" E. Upper Kimmeridgian. 

Opisthotrigonia curta (Aitken), Astarte weissermeli Dietrich, Seebachia janenschi 
Dietrich. 

Mpilepile stream, below 2nd confluence on N. side, 1300 yards E.N.E. of Mitole 
road junction, northern Mandawa area (B.P. loc. RS 815). 9 16' 3" S., 39 ° 24' 
1" E. Upper Kimmeridgian. 
Astarte mitoleensis sp. nov. 

Mpilepile stream bed, running E. from Mitole, 200 yards S.E. of a point 1300 yards 
E.N.E. of Mitole road junction, northern Mandawa area (B.P. loc. RS 816). 9 15' 
56" S., 39° 24' 23" E. Upper Kimmeridgian. 
Chlamys (Radulopectenl) kinjeleensis sp. nov. 

Mpilepile stream bed, running E. from Mitole, just below confluence on S. side, 
1650 yards N.E. of Mitole road junction, northern Mandawa area (B.P. loc. RS 817). 
9 15' 56" S., 39° 24' 32" E. Upper Kimmeridgian. 
Nummocalcar mitoleensis sp. nov. 

Kiwawa stream, 2400 yards S.E. of Mitekera survey beacon, northern Mandawa 
area (B.P. loc. RS 838). 9 14' 44" S., 39 ° 19' 36" E. Upper Kimmeridgian. 

Chlamys (Radulopecten?) kinjeleensis sp. nov., Myophorella kiwawaensis sp. nov. 

Near site of Mandawa well no. 1 (B.P. loc. PEK 5798). 9 18' 43" S., 39 ° 22' 35" E. 
Bajocian (?), Pindiro Shales. 

Gervillella orientalis (Douville), Pinna buchii Koch & Dunker, Astarte kenti sp. 
nov., Mactromya eamesi sp. nov., Pronoella pindiroensis sp. nov., Coelostylina 
mandawaensis sp. nov., Pictavia tanganyicensis sp. nov., Ampullospira besairiei 
sp. nov., Zygopleura mandawaensis sp. nov., Exelissa africana sp. nov., Pietteia 
sp., Acteonina sp. 

About 1 mile E.S.E. of Uleka, Mavudyi-Namgaru area (B.P. loc. JOZ 189). 9 
51' 33" S., 39 27' 30" E. " Jurassic ", stage uncertain. 
Eomiodon namgaruensis sp. nov. 



182 JURASSIC BIVALVIA AND GASTROPODA 

N. bank of Mandawa-Namakongoro stream, between telegraph line and Lindi- 
Kilwa road, about i mile W. of Mandawa (loc. WA 794). 9 22' 24" S., 39 ° 26' 9" E. 
M.-U. Kimmeridgian. 

Bathrotomaria aitkeni sp. now 

N. bank of Mandawa-Namakongoro stream, about 1 mile W. of Mandawa (loc. 
WA 812, WA 2001). 9 22' 24" S., 39° 26' 6" E. M.-U. Kimmeridgian. 
Pseudomelania (Oonia) aitkeni sp. no v., Nerinella mandawaensis sp. nov. 

Along Mandawa-Namakongoro stream, about 200 yards above confluence with 
Mandawa stream (loc. WA 817). 9 22' 28" S., 39 26' 4" E. M.-U. Kimmeridgian. 
Bathrotomaria aitkeni sp. nov. 

Along Mandawa-Namakongoro stream, about £ mile above confluence with Man- 
dawa stream (loc. WA 823). 9 22' 40" S., 39 26' 2" E. M.-U. Kimmeridgian. 
Bathrotomaria aitkeni sp. nov. 

About 1 mile N. of Manyuli, near Lindi-Kilwa road (loc. WA 944). 9 17' 58" S., 
39 24' 6" E. M.-U. Kimmeridgian. 
Pseudomelania vittata (Phillips). 

\\ miles N.W. of Mandawa (loc. WA 971). 9 21' 34" S., 39 26' 3" E., M.-U. 
Kimmeridgian. 

Lissochilus stremmei Dietrich. 

£ mile up Nchia stream, 2 miles W.N.W. of Mandawa (loc. WA 1005, 1180). 9 
21' 36" S., 39 25' 10" E. Callovian. 

Astarte aitkeni sp. nov., Pseudomelania aspasia (d'Orbigny), Bourguetia sae- 
manni (Oppel), Ampullospira quennelli sp. nov., Nerineidae, gen. et sp. indet. 

f mile N.W. of Mbinga (loc. WA 1156). 9 25' 43" S., 39° 26' 39" E. Upper 
Kimmeridgian. 

Purpuroidea aff. gigas (Thurmann & Etallon). 

Along Lonji-Runjo stream at a point i\ miles W. of Mandawa (loc. WA 1220). 
9° 22' 2" S., 39 25' 21" E. Callovian. 
Pseudorhytidopilus lonjiensis sp. nov. 

Along Lonji stream, a little E.N.E. of Nandenga hill (loc. WA 1287). 9 21' 44" S., 
39 24' 25" E. Bathonian-Upper Oxfordian part of Mandawa-Mahokondo Series ; 
probably Callovian. 
Globular ia sp. 

Along Lonji stream, a little E.N.E. of Nandenga hill (loc. WA 1345). 9 21' 46" S., 
39 24' 29" E. Callovian. 

Pseudomelania aff. aspasia (d'Orbigny), Ampullospira quennelli sp. nov. 



FROM TANGANYIKA AND KENYA 183 

Along Lonji stream, a little E.N.E. of Nandenga hill (loc. WA 1346). 9 21' 48" S., 
39° 24' 26" E. Callovian. 

Ampallospira quennelli sp. nov. 

Along Mbaru stream, 1 mile N.W. of Mbinga (loc. WA 1634). 9° 2 5' 36" S., 39 ° 
26' 16" E. Callovian. 

Harpagodes aff. oceani (Brongniart), Akera tanganyicensis sp. nov. 

Mpilipili stream at a point about 1 mile N.E. of Mitole (loc. WA 1691). 9 15' 40" 
S., 39° 24' 38" E. Upper Kimmeridgian. 
Chartronella mitoleensis sp. nov. 

Along Lihimaliao stream at a point about f mile E. of Njenja (loc. WA 1817). 
9 25' 17" S., 39° 24' 26" E. Upper Oxfordian (?). (A nearby locality was dated as 
Upper Oxfordian on ammonite evidence.) 

Grammatodon (Indogrammatodon) virgatus (J. de C. Sowerby). Nerinella ? 
muelleri Cox. 

Along Nchia stream, \ mile E. of Lonji (loc. WA 2013). 9 21' 25" S., 39 24' 45" E. 
Bathonian-Upper Oxfordian part of Mandawa-Mahokondo Series ; probably 
Callovian. 

Globularia sp. 

£ mile S. of Madaraha (loc. WA 2158). 9 20' 54" S., 39 ° 23' 24" E. Middle-Upper 
Kimmeridgian. 

" Pleurotomaria " sp. 

Manyuli stream at a point just W. of Nautope, Mandawa-Mahokondo anticline 
(loc. WA 2162). 9 17' 40" S., 39° 23' 35" E. Callovian. 

Eopecten aubryi (Douville), Entolium corneolum (Young & Bird), Harpagodes aff. 
oceani (Brongniart). 

Along Nunga stream, a short distance upstream from confluence with Manyuli 
stream, f mile N.W. of Nautope (loc. WA 2258). 9 17' 23" S., 39° 23' 11" E. Bath- 
onian-Upper Oxfordian part of Mandawa-Mahokondo Series ; probably Callovian. 
Harpagodes aff. oceani (Brongniart). 

About 1 mile E. of Manyuli (loc. WA 2261). 9 19' 10" S., 39 ° 26' 10" E. Upper 
Kimmeridgian. 

" Pleurotomaria " sp. 

E. of Bwatabwata village, Pindiro area (loc. WA 2273). 9 29' 48" S., 39 17' 47" 
E. (Aitken 1961 : 17). Bajocian (?), Pindiro Shales. 
Protocardia sp. 



184 JURASSIC BIVALVIA AND GASTROPODA 

Along Namakumbira stream, \ mile E. of Madaraha (loc. WA 2296). 9 20' 26" S., 
39° 23' 52" E. Bathonian-Upper Oxfordian part of Mandawa-Mahokondo Series. 
Amphitrochus ? sp. 

Along Namakumbira stream, | mile N. of Madaraha (loc. WA 2298). 9 20' 18" 
S.j 39° 23' 45" E. Bathonian-Upper Oxfordian part of Mandawa-Mahokondo Series. 
" Pleurotomaria " sp. 

I mile E. of Nangororo (loc. WA 2305). 9 31' 10" S., 39 19' 51" E. Upper 
Kimmeridgian. 

Pseudonerinea clio (d'Orbigny), Globularia aff. phasianelloides (d'Orbigny). 

Namakambe stream, Mandawa-Mahokondo anticline (loc. WA 2307). 9 23' 32" 
S., 39 24' 40" E. Probably Callovian. 

Chlamys (Spondylopecten?) badiensis Cox. 

Mbaru stream, N.E. of Nondwa and about \ mile upstream from crossing of tele- 
graph line, Mandawa-Mahokondo area (loc. WA 2349). 9 25' 16" S., 39 25' 48" E. 
Bajocian (?), Pindiro Shales. 

Corbula ? sp., Procerithiidae. 

Tributary of Namakumbira stream, 1 mile S.E. of Mkomore, Mandawa-Mahokondo 
area (Iocs. WA 2377, WA 2378). 9 19' o" S., 39 ° 23' 28" E. Bajocian (?), Pindiro 
Shales. 

Astarte pindiroensis sp. nov., Corbula sp. 

Localities in the Hinterland of Dar es Salaam and Bagamoyo, 

Tanganyika 

Quarries about 1 mile N.N.E. of Ngerengere, Central Railway. 6° 45' S., 38 8' E. 
(Quennell et al., 1956 : 126). Bajocian (?). 

Mytilus? sp., Bakevellia iraonensis (Newton), Eomiodon baroni (Newton), 
Eomiodon tanganyicensis sp. nov., Tancredia sp. 

1$ miles N.N.W. of Kidugallo, Central Railway (B.P. loc. JCS 108). 6° 46' 15" S., 
38 ° 12' 48" E. Bajocian. 

Trigonia kidugalloensis sp. nov., Pronoella kidugalloensis sp. nov. 

2\ miles N.N.W. of Kidugallo, Central Railway (B.P. loc. JCS 124). 6° 45' 35" S., 
38 ° 13' 30" E. Bajocian. 

Pseudomelania (Oonia) kidugalloensis sp. nov., Coelostylina stockleyi sp. nov. 

Magole, 5 miles N.W. of Kidugallo, Central Railway (B.P. loc. JCS 114, 115, 116, 
117). 6° 44' 22" S., 38 15' 15" E. Bajocian. 



FROM TANGANYIKA AND KENYA 185 

Trigonia costata Parkinson, Eotrapezium?. kenti sp. nov., Corbula kidugalloensis 
sp. nov. 

6 miles N.W. of Kidugallo, Central Railway (B.P. loc. JCS 120). 6° 44' 35" S., 
38 ° 8' 37" E. Bajocian. 

Eomiodon baroni (Newton), Corbula earnest sp. nov. 

6 miles N.W. of Kidugallo, Central Railway (B.P. loc. JCS 155). 6° 44' 35" S., 
38 ° 8' 10" E. Bajocian. 
Trigonia kenti sp. nov. 

Kidugallo Station, Central Railway. 6° 47' S., 38 12' 30" E. (Quennell el al., 
1956 : 186). Bajocian, Station Beds. 

Grammatodon sp., Modiolus anatinus Smith, Pinna sp., Bositra buchi (Roemer), 
Entolium sp., Chlamys sp., Lima (Plagiostoma) sp., Lucina despeda Phillips, 
Madromya sp., Pholadomya lirata (J. Sowerby), Osteomya dilata (Phillips). 

Rest house, Kidugallo, Central Railway. 6° 47' S., 38° 12' 30" E. (Quennell et al., 
1956 : 186). Bajocian, Station Beds. 

Grammatodon sp., Parallelodon sp., Astarte sp., Madromya ? sp., Protocardia sp., 
Eotrapezium ? sp., Tancredia sp., Ceratomya sp., Ataphrus aff. acmon (d'Orbigny). 

Borehole 5 miles N. of Kidugallo, Central Railway. 6° 43' S., 38 12' E. (Arkell 
J 956 : 33°) • Lower Bajocian (Aalenian). 
Bositra buchi (Roemer). 

ij miles E. of Kidugallo Station, Central Railway (loc. M 47). 6° 47' S., 38 13' E. 
Bajocian, Station Beds. 

Modiolus anatinus Smith, Chlamys sp., Lopha gregarea (J. Sowerby), Astarte sp., 
Lucina despeda Phillips, Fimbria kidugalloensis sp. nov., Protocardia sp., 
Pholadomya lirata (J. Sowerby), Goniomya trapezicostata (Pusch), Thracia sp. 

3 miles N.E. of Kidugallo Station, Central Railway (loc. M 46). 6° 46' S., 38 14' 
E. Bajocian, Station Beds. 

Lima {Plagiostoma) sp., Globularia sp. 

2 miles W. of Magindu Station, Central Railway (loc. M 48). 6° 49' S., 38 17' E. 
About Bathonian. 

Liostrea dubiensis (Contejean). 

1 mile W. of Magindu Station, Central Railway (loc. M 49). 6° 49' S., 38 ° 18' E. 
About Bathonian. 

Liostrea dubiensis (Contejean). 



[86 JURASSIC BIVALVIA AND GASTROPODA 

Magindu, Central Railway (B.P. loc. PEK 5805). 6° 48' 45" S., 38 19' 7" E. 
Callovian. 

Liostrea (Catinula) alimena (d'Orbigny), Ceratomya pittieri (de Loriol). 

E. of Magindu Station, Central Railway (loc. D 30), 6° 49' S., 38 20' E. Callo- 
vian. 

Liostrea sp. 

About 2 km. E. of Magindu, Central Railway (B.P. loc. PEK 5806). 6° 49' S., 
38 ° 20' 15" E. Callovian. 

Liostrea (Catinula) alimena (d'Orbigny). 

2 miles E. of Magindu Station, Central Railway (loc. D 31). 6° 49' S., 38 22' E. 
Callovian. 

Cer atomy opsis basochiana (Def ranee), Pholadomya lirata (J. Sowerby). 

2 miles E. of Magindu Station, Central Railway (Iocs. D. 34, D 36). 6° 49' S., 
38° 21' E. Callovian. 

Trigonia (Frenguelliella) tealei Cox, Astarte muelleri Dacque, Pholadomya lirata 
(J. Sowerby). 

Changogo-Magindu track, 4 miles from Changogo town (B.P. loc. PEK 5801). 
Callovian. 

Protocardia consobrina (Terquem & Jourdy). 

Borehole at Lugoba. Lower Bajocian (Aalenian). 
Bositra buchi (Roemer). 

Top of hill N. of Lugoba on Msata road (B.P. loc. RBH 671). 6° 22' 7" S., 38 21' 
47" E. Callovian (?). 

Praeconia rhomboidalis (Phillips). 

S. of Tarawanda, n miles S.E. of Lugoba (Iocs. B 3, B 4, B 5) (Quennell et al., 1956 : 
181). Callovian. 

Grammatodon (Indogrammatodon) stockleyi Cox, Gervillella ? sp., Meleagrinella 
echinata (Smith), Chlamys subtextoria (Miinster), Trigonia (Frenguelliella) tealei 
Cox, Neritoma (Neridomus) aff. gea (d'Orbigny), Pseudomelania (Oonia) sp. 

\ mile from Msata on road to Bagamoyo (B.P. loc. PEK 5406). 6° 19' 45" S., 38° 
23' 30" E. Callovian or Oxfordian. 
Lopha eruca (Defrance). 

z\ miles N. of Msaka road junction, Bagamoyo district (B.P. loc. JOZ 465). 6° 17' 
30" S., 38 ° 23' 37" E. Callovian. 
Entolium briconense (Cossmann). 



FROM TANGANYIKA AND KENYA 187 

Usigiwa river, 6 miles W.S.W. of Kiwangwa, Bagamoyo hinterland (loc. BM 29). 
6° 24' 19" S., 38 30' 23" E. Upper Oxfordian. 

Parallelodon sp., Pteria tanganyicensis sp. nov., Meleagrinella radiata (Traut- 
schold), Limatula moorei sp. nov., Trigonia (Frenguelliella) tealei Cox, Astarte 
episcopalis de Loriol, Fimbria quennelli sp. nov., Isocyprina ? sp. , Pseudotrapezium 
sp., Cercomya sp. 

Scarp face, eastern margin of Makoko plain, f mile S. of Wami river, Bagamoyo 
hinterland (loc. BM 43). 6° 16' o" S., 38 ° 30' 47" E. Upper Oxfordian. 

Entolium corneolum (Young & Bird), Protocardia ? sp., Pleitromya uniformis (J. 
Sowerby), Bonrguetia saemanni (Oppel). 

In small stream on scarp face, eastern margin of Makoko plain, 1 mile S. of Wami 
river, Bagamoyo hinterland (loc. BM 45). 6° 16' 14" S., 38 30' 50" E. Oxfordian. 
Grammatodon (I ndogrammatodon) stockleyi Cox, Trichites sp., Trigonia {Fren- 
guelliella) tealei Cox, Goniomya liter ata (J. Sowerby). 

Top of scarp face on eastern margin of Makoko plain, 1 J miles S. of Wami river, 
Bagamoyo hinterland (loc. BM 46). 6° 16' 41" S., 38 31' 0" E. Oxfordian. 
Pleuromya uniformis (J. Sowerby). 

Kiwate-Mkange track 5 miles S.S.E. of Mkange (loc. BM 95). 6° 7' 37" S., 38 
34' 52" E. Oxfordian-Kimmeridgian. 

Meleagrinella radiata (Trautschold), Liostrea dubicnsis (Contejean), Exogrya nana 
(J. Sowerby), Astarte sp., Fimbria sp. 

Look-out hill opposite Kingura village, | mile N. of Wami river, Bagamoyo hinter- 
land (loc. BM 144). 6° 14' 25" S., 38 30' 58" E. Upper Oxfordian. 
Gryphaea hennigi Dietrich. 



Localities in N.E. Tanganyika 

b\ miles N.E. of Pande (village on Mkwaja-Mkata road) and z\ miles N. of 
Msangasi stream (loc. BM 292A). 5 45' 15" S., 38 39' 10" E. Callovian. 

Oxytoma ? sp., Pinna mitis Phillips, Chlamys (Aequipecten) cf. palintirus 
(d' Orbigny), Chlamys sp. 

Nearly z\ miles S.S.W. of Tengeni (village on Pangani river), in southernmost 
headwater tributary of Mbuzi Mkubwa stream (loc. BM 330). 5 25' 39" S., 38 39' 
33" E. Age uncertain. 

Bositra buchi (Roemer). 



188 JURASSIC BIVALVIA AND GASTROPODA 

2 miles W. of Tengeni (village on Pangani river), in Mbuzi Mkubwa stream (loc. 
BM 333). 5° 24' 42" S., 3 8° 39' 35" E. Bathonian (?). 

Pseudomelania (Oonia) conica (Morris & Lycett), Cryptaulax bussagensis (Coss- 
mann), " Nerinea " sp., Naricopsina sp. 

ii miles W.N.W. of Mremere (village on Pangani river) (loc. AT 431). 5° 24' o" S., 
38 ° 50' 14" E. Upper Oxfordian. 
Rollieria ? sp., Lopha sp. 

About 5 miles N.E. of Tengeni (village on Pangani river), at S. end of divide 
separating western tributary from main Maweni valley (loc. BM 369). 5 22' o" S., 
38 ° 44' 51" E. Upper Jurassic. 

Entolium cingulatum (Goldfuss). 

Chinamba, f mile S. of Amboni quarries, Tanga (B.P. loc. ANT 4506). 5 4' 38" S., 
39° 3' 3" E. Callovian. 

Oxytoma inequivalvis (J. Sowerby), Trigonia (Frenguelliella) tealei Cox. 

\ mile N.W. of bridge over Mkulumuzi river, 2 miles W. of Tanga (B.P. loc. PEK 
5402). 5 3' 42" S., 39 3' 25" E. Callovian. 

Grammatodon (Indogrammatodon) virgatus (J. de C. Sowerby), Chlamys (Spondy- 
lopecten ?) badiensis Cox, Goniomya trapezicostata (Pusch), Modiolus bipartitus 
J. Sowerby. 

Just W. of Mabokweni, 4 miles N.W. of Tanga (loc. QA 384). 5 1' 23" S., 39 3' 
o" E. Kimmeridgian. 

Gervillella aviculoides (J. Sowerby), Myophorella quennelli sp. nov., Mactromya 
quadrata (Roemer), Pholadomya protei (Brongniart), Ampullospira quennelli sp. 
nov. 



Localities in the Coastal District of Kenya 

Plantations N. of Dakatcha village, Malindi district (Iocs. 66/337, 66/338). 3 00' 
S., 39 48' E. (Williams 1962 : 17). Boulders, not in situ. Upper Jurassic. 

M eleagrinella radiata (Trautschold), Chlamys} sp., Quenstedtial sp., Isocyprinasp. 

1 mile E. of Merikano, Malindi district (loc. 66/129). 3 8' S., 39 50' E. (Thomp- 
son 1956 : 18). Boulders, not in situ. Upper Jurassic. 

M eleagrinella radiata (Trautschold). 

2 miles N.E. of Dakatcha, Malindi district (loc. 66/150). 2° 59' S., 39 49' E. 
Boulders, not in situ. Upper Jurassic. 

M eleagrinella radiata (Trautschold). 



FROM TANGANYIKA AND KENYA 189 

Chamgamwe, near Mombasa, c. 4 2' S., 39° 38' E. Kimmeridgian, Chamgamwe 
Shales. 

Lopha solitaria (J. de C. Sowerby). 

Kaya Kauma, 8 miles W. of Kilifi. 3 37' S., 39 44' E. (Parsons 1929 : 69). 
Callovian, Miritini Shales. 
Bositra buchi (Roemer). 



Localities in N.E. Kenya 

Didimtu hill, 2 miles N.E. of Bur Mayo (Iocs. 23/12, 23/355-357). 2 ° 57' N., 
40 ° 16' E. (Ayers 1952 : 27 ; Thompson & Dodson i960 : 20-24). Upper Lias, 
Toarcian, Didimtu Beds. 

Nuculana (Dacryomya) thompsoni sp. nov., Nuculana (Ryderia) kenyana sp. nov., 
Rollieria aequilatera (Koch & Dunker), Grammatodon kenyanus sp. nov., Modiolus 
(Inoperna) sowerbianus (d'Orbigny), Gervillella didimtuensis sp. nov., Weyla 
ambongoensis (Thevenin), Lopha costata (J. de C. Sowerby), Lopha olimvallata 
nom. nov., Astarte lurida J. Sowerby, Astarte pulfreyi sp. nov., Astarte didimtu- 
ensis sp. nov., Astarte subminima sp. nov., Astarte sp., Astarte (Leckhamptonia) 
hobleyi sp. nov., Lucina sp., Protocardia africana sp. nov., Anisocardia arkelli sp. 
nov., Anisocardia didimtuensis sp. nov., Anisocardia ayersi sp. nov., Eotrapezium ? 
africanum sp. nov., Eotrapezium ? thompsoni sp. nov., Corbula didimtuensis sp. 
nov., Pholadomya reticulata Agassiz, Pleuromya didimtuensis sp. nov., Disco- 
helix didimtuensis sp. nov., Africoconulus kenyanus sp. nov., Trochopsidea 
africana sp. nov., Hamusina thompsoni sp. nov., Purpuroidea supraliasica sp. 
nov., Promathildia aff. opalini (Quenstedt), Acteonina (Striactaeonina) supra- 
liasica sp. nov. 

Camel track about 5 miles S. of Singu and 9 miles E. of Tarbaj (loc. 23/112). 2° 
13' N., 40 16' E. (Thompson & Dodson i960 : 23). Toarcian or Bajocian, top of 
Didimtu Beds, just below Bur Mayo Limestones. 
Nuculana (Praesaccella) camelorum sp. nov. 

2 miles W. of Melka Biini and 16 miles W.N.W. of Rahmu (loc. 8/8). 4 3' N., 
41° 2' E. (Joubert i960 : 12). Bathonian, Murri Limestones. 

Brachidontes (Arcomytilus) asper (J. Sowerby), Chlamys curvivarians (Dietrich), 
Lima (Plagiostoma) biiniensis sp. nov., Ostrea (Liostrea) sp. 

Hagardulun, 25 miles N.E. of Tarbaj (loc. 23/116). 2° 29' N., 40 22' E. (Thomp- 
son & Dodson i960 : 32). Bathonian-Callovian, Bur Mayo Limestones. 

Nuculana [Dacryomya) dodsoni sp. nov., Brachidontes {Arcomytilus) sp., Lima 
(Plagiostoma) sp., Trigonia sp., Pholadomya ovalis (J. Sowerby), Ceratomya sp. 
Exelissa dodsoni sp. nov. 



i go 



Jl'RASSIC BIVALVIA AND GASTROPODA 





39" 


W _ 41- 








Me 

r 


lka Murrii^P, 


Melka 
Dakacha ** 


V — 






/ 


y^ • Ra> mu* Sndera 














fe::::-:-::-::-:-:::-:::: 


•** V 


Wergudud* 






| V El Wak 

V : :': : : : : : : : : : : ; : : ' ; : ; : : . : :vX : j 


r — 






« 


t^u^— j 2" 

i 
I 

j 

i 
i 










; 




100 D 


liles 


>, 


I 

! 






j 












i 
































^ 




\y 


2' 






















gr^ — ^ 


3' 




















HB Malindi 


3 


. 






)m 


Cilifi 




V s -.. 


i 




Mombasa 


















39 




tt 


'.1 


• 



Fig. 2. Sketch-map of eastern Kenya, showing Jurassic outcrops. 



FROM TANGANYIKA AND KENYA 191 

Kurawe, 2 miles E. of Hagardulun, 25 miles N.E. of Tarbaj (loc. 23/78). 2° 29' N., 
40° 25' E. (Thompson & Dodson i960 : 32). Bathonian-Callovian, Bur Mayo Lime- 
stones. 

Lima (Plagio stoma) sp., Thracia sp. 

1 mile N. of Asaharbito, 28 miles N. of Wergudud (loc. 15/28). 3 33' N., 40 
57' E. (Ayers 1952 : 22 ; Thompson & Dodson 1958 : 21). Bathonian [? or Callo- 
vian], Asaharbito Beds. 

Nucula sp., Grammatodon sublaevigatus (Zieten), Barbatia sp., Liostrea dubiensis 
(Contejean), Trigonia cf. brevicostata Kitchin, Astarte ayersi sp. nov., Sphaeriola 
madridi (d'Archiac), Isocyprina ? sp., Anisocardia ? sp., Corbula asaharbitensis sp. 
nov., Arcomya ? sp., Pleuromyasp., Cuspidaria ayersi sp. nov., Aporrhaidae, gen. 
indet. 

3! miles W. of Melka Biini and 17 miles W.N.W. of Rahmu, hills N. of Rahmu- 
Melka Murri road (loc. 8/7). 4 3' N., 41 1' E. (Joubert, i960 : 15). Callovian, 
Rukesa Shales. 

Eopecten aubryi (Douville), Chlamys curvivarians (Dietrich), Lopha gregarea 
(J. Sowerby), Lopha costata (J. de C. Sowerby), Liostrea (Catinula) alimena 
(d'Orbigny), Mactromya aequalis Agassiz, Protocardia sp., Homomya inornata 
(J. de C. Sowerby), Ceratomya concentrica (J. de C. Sowerby), Globidaria sp., 
Cylindrites ? sp. 

3! miles W. of Melka Biini and 17 miles W.N.W. of Rahmu, hills N. of Rahmu- 
Melka Murri road (loc. 8/5). 4 3' N., 41 ° 1' E. (Ayers 1952 : 24 ; Joubert i960 : 
13). Callovian, Rukesa Shales. 

Lopha sp., Fimbria sp., Protocardia sp., Quenstedtia sp. 

3 miles W. of Melka Biini and 16 miles W.N.W. of Rahmu, hills N. of Rahmu- 
Melka Murri road (loc. 8/9). 4 3' N., 41 1' 30" E. Callovian, Rukesa Shales. 
Lopha sp., Pholadomya lirata (J. Sowerby), Cercomya sp. 

13 miles W. of Rahmu, hills 4 miles S. of road to Melka Murri (loc. 16/178). 3 
58' N., 41 ° 2' E. (Joubert i960 : 15). Callovian, Rukesa Shales. 

Lopha gregarea (J. Sowerby), Fimbria sp. " A ", Pholadomya sp. 

13 miles W. of Rahmu, hills 2 miles S. of road to Melka Murri (loc. 16/179). 3 
59' N., 41° 2' E. (Joubert i960 : 15). Callovian, Rukesa Shales. 

Lima (Plagiostoma) cf. schardti de Loriol, Lopha gregarea (J. Sowerby), Cerato- 
myopsis basochiana (Defrance), Anisocardia minima (J. Sowerby). 

11 miles W. of Rahmu, hills S. of road to Melka Murri (loc. 16/176). 3 59' N., 
41 ° 5' E. (Joubert i960 : 15). Callovian, Rukesa Shales. 

Eonavicula sp., Eopecten sp., Chlamys sp., Lima (Plagiostoma) sp., Lopha gre- 
garea (J. Sowerby), Mactromya sp., Fimbria sp. " A ", Protocardia sp. 



i 9 2 JURASSIC BIVALVIA AND GASTROPODA 

Bed of Muddo river, 4 miles S.W. of Muddo Erri (loc. 16/195). 3 53' N., 41° o' E. 
(Joubert i960 : 18). Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Lima (Plagiostoma) sp., Eligmus rollandi Douville^ Fimbria sp., Mactromya sp. ( 
Globularia sp. 

Kulong, 2 miles S.W. of Muddo Erri, 12 miles W. of Rahmu (loc. 16/189). 3° 54' 
N., 41 ° 2' E. (Joubert i960 : 18). Callovian [?-Lower Oxfordian], Muddo Erri 
Limestones. 

Brachidontes (Arcomytilus) asper (J. Sowerby), Brachidontes (Arcomytilus) lait- 
mairensis (de Loriol), Eligmus rollandi Douville, Entolium corneolum (Young & 
Bird), Eopecten aubryi (Douville), Camptonectes auritus (Schlotheim), Chlamys 
curvivarians (Dietrich), Lima (Plagiostoma) cf. biiniensis sp. nov., Lima (Plagio- 
stoma) cf. jumaraensis Cox, Lima (Plagiostoma) cf. schardti de Loriol, Lima 
(Plagiostoma) sp., Pseudolimea duplicata (J. de C. Sowerby), Liostrea sp., Liostrea 
(Catinnla) alimena (d'Orbigny), Trigonia sp., Lucina cf. lirata Phillips, Mactro- 
mya aequalis Agassiz, Fimbria sp. " B ", Protocardia sp., Ceratomyopsis basochi- 
ana (Defrance), Pholadomya ovalis (J. Sowerby), Pholadomya sp., Ceratomya 
concentrica (J. de C. Sowerby). 

Muddo Erri, 12 miles W. of Rahmu (loc. 16/172). 3 56' N., 41 4' E. (Joubert 
i960 : 18). Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Eonavicula sp. " A ", Eligmus rollandi Douville, Eopecten aubryi (Douville), 
Chlamys sp., Lima (Plagiostoma) muddoensis sp. nov., Mactromya aequalis 
Agassiz, Fimbria sp. " A ", Fimbra sp. " B ", Protocardia ? sp. 

14 miles W.S.W. of Rahmu (loc. 16/41). 3 52' N., 41 2' E. (Ayers 1952 : 23). 
Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Eligmus rollandi Douville, Lima (Plagiostoma) sp., Exogyra ? sp., Mactromya 
aequalis Agassiz, Fimbria ? sp., Homomya sp., Ceratomya wimmisensis GiWievon. 

9 miles W. of Rahmu, hills S. of Rahmu-Melka Murri road (loc. 16/175). 3 59' 
N., 41 ° 6' E. Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Lima (Plagiostoma) sp., Fimbria sp. " A ". 

10 miles W. of Rahmu, top of hills S. of Rahmu-Melka Murri road (loc. 16/139). 
3 59' N., 41 5' E. Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Camptonectes auritus (Schlotheim), Chlamys curvivarians (Dietrich), Liostrea 
(Catinula) alimena (d'Orbigny), " Pleurotomaria " sp., Nerineidae, gen. indet. 

6 miles W. of Rahmu, hillside S. of Rahmu-Melka Murri road (loc. 16/162). 3° 
58' N., 41 ° 9' E. Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 

Eligmus rollandi Douville^ Eopecten aubryi (Douville^, Lima (Plagiostoma) sp., 
Lopha gregarea (J. Sowerby), Lopha costata (J. de C. Sowerby). 



FROM TANGANYIKA AND KENYA 193 

River section west of Rahmu-El Wak road, 5^ miles S.W. of Rahmu (loc. 16/164, 
16/146). 3 52' N., 41° 12' E. (Joubert i960 : 20). Oxfordian, Rahmu Shales. 
Grammatodon (Indogrammatodon) sp., Lopha solitaria (J. de C. Sowerby), 
Protocardia rahmuensis sp. nov. 

6\ miles S.S.W. of Rahmu (loc. 16/44). 3° 5 2 ' N -> 4 1 " I0 ' E - (Ayers 1952 : 26). 
Oxfordian, Rahmu Shales. 

Lopha sp., Lopha gregarea (J. Sowerby), Lopha cf. intricata (Contejean). 

if miles S.W. of Rahmu (Iocs. 16/66, 16/67). 3° 54' N., 41 ° 12' E. (Ayers 1952 : 
25). Oxfordian, Rahmu Shales. 

Lopha gregarea (J. Sowerby), Lopha solitaria (J. de C. Sowerby). 

2| miles S.W. of Rahmu (loc. 16/64). 3° 5 2 ' 3°" N., 41 ° 12' E. (Ayers 1952 : 25 ; 
Joubert i960 : 19). Oxfordian, Rahmu Shales. 

Mytilus (Falcimytilus) jurensis Roemer, Stegoconcha sp., Camptonectes auritus 
(Schlotheim), Lima (Plagiostoma) rahmuensis sp. nov., Exogyra nana (J. 
Sowerby), Isocyprina sp. 

Uacha, 6 miles S. of Rahmu (loc. 16/219). 3°5i'N., 41 13' E. (Joubert i960 : 20). 
Oxfordian, Rahmu Shales. 

Protocardia rahmuensis sp. nov., Homomya rahmuensis sp. nov. 

Muguda, 24 miles S.W. of El Wak (loc. 23/217). 2° 31' N., 40 43' E. (Baker & 
Saggerson 1958 : 18). Oxfordian (?). 
Entolium sp., Chlamys sp. 

Waldire, 20 miles N.E. of Aus Mandula (loc. 23/250, 23/252). 2° 28' N., 40 46' E. 
(Baker & Saggerson 1958 : 18). Oxfordian (?). 

Entolium corneolum (Young & Bird), Protocardia sp. 

Romicho, 25 miles S.W. of El Wak. 2 36' N., 40 ° 39' E. (loc. 23/275-277) 
(Baker & Saggerson 1958 : 18). Oxfordian, beds immediately underlying Golberobe 
Beds. 

Cucullaea (Megacucullaea ?) sp., Mytilus {Falcimytilus) jurensis Roemer. 

Golberobe hills, half-way between Wergudud and Takabba (loc. 15/227-228). 3 
23' N., 40 32' E. Oxfordian, Golberobe Beds. 

Lopha sp., Lopha solitaria (J. de C. Sowerby), Liostrea dubiensis (Contejean). 

Korkai Hammassa, 19 miles E. of Takabba (loc. 15/443-466). 3 22' N., 40 29' 
E. (Saggerson & Miller 1957 : 14). Oxfordian, Golberobe Beds. 

Nucula sp., Modiolus imbricatus (J. Sowerby), Modiolus (Inoperna) sowerbianus 
(d'Orbigny), Gervillia saggersoni sp. nov., M eleagrinella radiata (Trautschold) , 



194 JURASSIC BIVALVIA AND GASTROPODA 

Lopha tifoensis sp. nov., Trigonia sp., Astarte sp., Mactromya sp., Protocardia sp., 
Isocyprina ? sp., Tancredia sp. " A ", Quenstedtia sp., Cercomya sp. 

Ogar Wein hills, 17 miles N.W. of Wergudud (loc. 15/535-575). 3° 2 4' N., 40 45' 
E. (Saggerson & Miller 1957 : 14, 23). Oxfordian, Golberobe Beds. 

Cucullaea sp., Mytilus [Falcimytilus] tifoensis sp. nov., Gervillia saggersoni sp. 
nov., Meleagrinella radiata (Trautschold), Liostrea dubiensis (Contejean), 
Exogyra nana (J. Sowerby), Lopha tifoensis sp. nov., Tancredia sp. " B ", 
Quenstedtia sp. 

Tifo, Garri hills, 14 miles N. of Wergudud (loc. 15/380-441, 15/584-586). 3 23' 
N., 40° 56' E. (Saggerson & Miller 1957 : 14, 42). Oxfordian, Golberobe Beds. 

Modiolus imbricatus (J. Sowerby), Modiolus (Inoperna) sowerbianus (d'Orbigny), 
Mytilus [Falcimytilus] tifoensis sp. nov., Mytilus [Falcimytilus] dietrichi sp. nov., 
Brachidontes [Arcomytilus] laitmairensis (de Loriol), Gervillella siliqua (Eudes- 
Deslongchamps), Inoceramus sp., Placunopsis sp., Exogyra nana (J. Sowerby), 
Lopha tifoensis sp. nov., Lopha sp., Trigonia sp., Protocardia sp. 

Kailta, Golberobe hills, 22 miles E. of Takabba (Iocs. 15/599, I 5/6i3)- 3° 20' 7" N., 
40 31' E. (Saggerson & Miller 1957 : 12, 13, 42). Oxfordian, Golberobe Beds. 
Mactromya quadrata (Roemer), Mactromya sp., Corbula kailtaensis sp. nov. 

Asahaba, 19 miles N.N.E. of Wergudud (Iocs. 15/229, 230). 3 26' N., 40 58' E. 
(Saggerson & Miller 1957 : 23). Oxfordian, Golberobe Beds. 
Inoceramus sp., Lopha sp., Lopha tifoensis sp. nov. 

Chimpa, 20 miles N.W. of Wergudud (loc. 15/223). 3 25' N., 40 35' 30" E. 
(Saggerson & Miller 1957 : 14). Oxfordian, Golberobe Beds. 
Meleagrinella radiata (Trautschold), Lopha tifoensis sp. nov. 

Dirahara, 24 miles E.N.E. of Aus Mandula (loc. 23/280, 281). 2 22' N., 40 53' E. 
(Baker & Saggerson 1958 : 19, 23). Oxfordian, Golberobe Beds. 
Mytilus [Falcimytilus] dietrichi sp. nov. 

3 miles E. of Waldire, 24 miles N.E. of Aus Mandula (loc. 23/258). 2° 29' N., 40 
49' E. (Baker & Saggerson 1958 : 22). Oxfordian, Golberobe Beds. 
Protocardia sp. 

8 miles N.W. of Ogar Wein hills (loc. 15/38^). 3 22' N., 40 39' E. (Ayers 1952 : 
23). Horizon uncertain. 

Meleagrinella radiata (Trautschold). 

Danissa, 8 miles N. of Wergudud (loc. 15/592). 3 19' N., 4 52' E. (Saggerson & 
Miller 1957 : 42). Horizon uncertain. 
Quenstedtia sp. 



FROM TANGANYIKA AND KENYA 195 

17 miles S. of Rahmu (loc. 16/190). 3 40' N., 41 ° n' E. (Joubert i960 : 24). 
Upper Oxfordian, Seir Limestones. 

Meleagrinella radiata (Trautschold) , Mactromya quadrata (Roemer) . 

7 miles N.N.E. of Raiya hills (loc. 16/16). 3 52' N., 41 26' E. (Ayers 1952 : 26). 
Upper Oxfordian, Seir Limestones. 
Eopecten thurmanni (Brauns). 

Koblollo, 15 miles S.S.W. of Rahmu (loc. 16/217). 3 45' N., 41 8' E. Upper 
Oxfordian, Seir Limestones. 

Procerithiidae, etc. genera indet. 

Wilderri hill, 11 miles S.S.W. of Rahmu (loc. 16/145). 3 47' N., 41 9' 30" E. 
(Joubert i960 : 23). Upper Oxfordian, Seir Limestones. 

Grammatodon (Indogrammatodon) stockleyi Cox, Modiolus (Inoperna) sp., 
Entolium corneolum (Young & Bird), Eopecten aff. albus (Quenstedt), Chlamys 
sp., Lopha gregarea (J. Sowerby), Lopha solitaria (J. de C. Sowerby), Exogyra sp., 
Anisocardia sp., Ceratomya wilderriensis sp. nov., Pseudomelania (Rhabdoconcha) 
wilderriensis sp. nov., Bourguetia saemanni (Oppel), Ampullospira dej antra 
(d'Orbigny), Harpagodes ? sp. 

Low hills at Dusse, i| miles S.E. of Rahmu (loc. 16/166). 3 55' N., 41 ° 15' E. 
(Joubert i960 : 23). Upper Oxfordian, Seir Limestones. 

Grammatodon (Indogrammatodon) irritans (Hennig), Mytilus (Falcimytilus) 
jurensis Roemer, Stegoconcha gmuelleri (Krenkel), Eopecten sp., Camptonectes 
auritus (Schlotheim), Chlamys (Radulopecten) inaequicostata (Young & Bird), 
Lima (Plagiostoma) sp., Pseudolimea duplicata (J. de C. Sowerby), Lopha solitaria 
(J. de C. Sowerby), Liostrea dubiensis (Contejean), Astarte huralensis Stefanini, 
Ceratomya wilderriensis sp. nov., Pseudomelania dusseensis sp. nov., Bourguetia 
saemanni (Oppel) , Pietteia dusseensis sp.nov., Ampullospira dejanira (d'Orbigny), 
Globularia phasianelloides (d'Orbigny). 

3 miles E. of Rahmu, hillside S. of road to Mandera (loc. 16/158). 3 56' N., 41 
17' E. Upper Oxfordian, Seir Limestones. 
Nerinella cutleri sp. nov. 

5 miles W.S.W. of Rahmu (loc. 16/57). 3° 54' N., 41 ° 10' E. (Ayers 1952 : 24). 
Horizon uncertain. 

Entolium corneolum (Young & Bird). 

6 miles N.N.E. of Raiya hills and 5 miles W.S.W. of Melka Kunha (loc. 16/17). 
3° 52' N., 41 ° 26' E. Kimmeridgian, Hereri Shales. 

Eopecten sp., Liostrea sp. 

Hereri river crossing, 3 miles S. of Melka Kunha, 16 miles E. of Rahmu (Iocs. 16/ 



ig6 JURASSIC BIVALVIA AND GASTROPODA 

150, 16/221). 3 55' N., 41 ° 28' E. (Joubert i960 : 26). Kimmeridgian, Hereri 

Shales. 

Grammatodon (Indogrammatodon) irritans (Hennig), Mytilus {Falcimytilus) 
jurensis Roemer, Eopecten thurmanni (Brauns), Chlamys curvivarians (Dietrich), 
Liostrea sp., Exogyra nana (J. Sowerby), Lucina sp., Protocardia (Tendagurium) 
bannesiana (Contejean), Ceratomyopsis striata (d'Orbigny), Ceratomya excent- 
rica (Roemer), Bourguetia saemanni (Oppel), Procerithiidae, Harpagodes sp. 

1 mile W. of Melka Dakacha (cited as " Daua valley 18^ miles E. of Rahmu ") 
(loc. 16/33). 3° 58' N., 41 29' 30" E. (Ayers 1952 : 26). Upper Kimmeridgian, 
Dakacha Limestones. 

Trochalia depressa (Voltz). 

6f miles S.W. of the Raiya hills and S.E. of Garba Raiya (loc. 16/52). 3 44' N., 
41 ° 20' E. Upper Kimmeridgian, Dakacha Limestones. 
Fimbria sp. 

N. of Figfirya, northern Raiya hills (loc. 16/165). 3 50' N., 41 ° 24' E. Upper 
Kimmeridgian, Dakacha Limestones. 

Liostrea sp., Protocardia sp., Quenstedtia jouberti sp. nov., Homomya sp., 
Harpagodes thirriae (Contejean), Globularia hemisphaerica (Roemer). 

1 mile S.W. of Melka Dakacha (cited as " S. of Rahmu-Mandera road, 19 miles E. 
of Rahmu ") ( loc. 16/31). 3 57' N., 41 30' E. (Ayers 1952 : 24). Upper Kim- 
meridgian, Dakacha Limestones. 

Harpagodes thirriae (Contejean). 

10J miles S.W. of the Raiya hills (loc. 16/55). 3° 43' N., 41 ° 14' E. (Ayers 1952 : 
24). Upper Kimmeridgian, Dakacha Limestones. 
Harpagodes thirriae (Contejean). 

3 miles N.E. of Melka Dakacha (loc. 16/201). 3 59' N., 41 33' E. (Joubert i960 : 
28). Upper Kimmeridgian, Dakacha Limestones. 

Modiolus virgulinus (Thurmann & Etallon), Modiolus (Inoperna) perplicatus 
(Etallon), Lopha gregarea (J. Sowerby), Myophorella sp., Rutitrigonia stefaninii 
Venzo, Mactromya quadrata (Roemer), Harpagodes thirriae (Contejean), Globu- 
laria hemisphaerica (Roemer). 

Melka Dakacha (loc. 16/192, 16/193). 3 57' N., 41 ° 31' E. (Joubert i960 : 28). 
Upper Kimmeridgian, Dakacha Limestones. 

Ctenostreon proboscideum (J. Sowerby), Globularia hemisphaerica (Roemer), 
Trochalia depressa (Voltz), Actaeonina ? sp. 

2 miles S. of Melka Dakacha (Iocs. 16/157, 16/209). 3 57' N., 41 ° 30' E. Upper 
Kimmeridgian, Dakacha Limestones. 



FROM TANGANYIKA AND KENYA 197 

Nuculoma (Palaeonucula) bellozanensis sp. nov., Pteria sp., Rutitrigonia stefaninii 
Venzo, Mactromya sp., Eocallista ? sp., Protocardia sp., Globularia hennigi sp. 
nov., Globularia phasianelloides (d'Orbigny). 

W. slope, Finno, Hegalu hills (loc. 16/130). 3 28' N., 41 31' E. (Joubert i960 : 
27, pi. 11, fig. 5). Upper Kimmeridgian, Dakacha Limestones. 

Camptonectes sp., Chlamys curvivarians (Dietrich), Lopha sp., Pholadomya sp. 

Hegalu hills, 2 miles N. of Finno (loc. 16/211). 3 28' 30" N., 41 32' E. (Joubert 
1960 : 26). Upper Kimmeridgian, Dakacha Limestones. 
Pholadomya hemicardia Roemer. 

5 miles S. of Galgali Gambo (loc. 16/29). 3° 53' N., 41 ° 22' E. (Ayers 1952 : 23). 
Upper Kimmeridgian, Dakacha Limestones. 

Lima (Plagiostoma) sublaeviuscula Krumbeck. 

Hill-top 1 mile W.S.W. of Melka Dakacha (loc. 16/147, 16/149). 3° 5 8 ' N -> 4 J ° 3°' 
E. Kimmeridgian, Hereri Shales overlain by Dakacha Limestones. 
Ceratomya excentrica (Roemer), Trochalia depressa (Voltz). 

Matasafara, 15 miles W. of Mandera (loc. 16/112). 3 58' N., 41 39' E. (Joubert 
i960 : 32, 34). Uppermost Jurassic, Gudediye Beds. 

Protocardia sp., Tancredia manderaensis sp. nov., Myopholas manderaensis sp. 
nov. 

W. slope of hill | mile E. of Hafura (loc. 16/129). 3 29' 30" N., 41 30' E. Upper- 
most Jurassic or basal Cretaceous, Danissa Beds. 
Trigonia dainellii Venzo. 

Odda (loc. 16/207). 3 39' N., 41 ° 23' E. (Joubert i960 : 40). Uppermost 
Jurassic or basal Cretaceous, Danissa Beds. 
Trigonia dainellii Venzo. 



ig8 JURASSIC BIVALVIA AND GASTROPODA 

VI REFERENCES 

Agassiz, L. 1842-45. Etudes critiques sur les mollusques fossiles. Monographie des Myes. 

xxii -f 287 pp., pis. ia-39. Neuchatel. 
Aitken, W. G. 1961. Geology and palaeontology of the Jurassic and Cretaceous of southern 

Tanganyika. Bull. geol. Surv. Tanganyika, Dar es Salaam, 31. vi + 144 pp., 14 pis. 
Archiac, A. d' 1843. Description geologique du departement de l'Aisne. Mdm.Soc. g60l.Fr., 

Paris, 5 : 129-418, pis. 21-31. 
Arkell, W. J. I92ga-37a. A monograph of British Corallian Lamellibranchia. xxxviii + 

392 pp., 55 pis. Palaeontogr. Soc. [Monogr.], London. 

1934&. The oysters of the Fuller's Earth ; and on the evolution and nomenclature of the 

Upper Jurassic catinulas and gryphaeas. Proc. Cotteswold Nat. Fid CI., Gloucester, 25 : 
21-68, pis. 1-6. 

1956. Jurassic geology of the world, xv + 806 pp., 46 pis. Edinburgh & London. 

Ayers, F. M. 1952. Geology of the Wajir-Mandera district, North-East Kenya. Rep. geol. 

Surv. Kenya, Nairobi, 22. 31 pp., 5 maps. 
Baumann, O. 1891. Usambara und seine Nachbargebiete. xi + 375 pp. Berlin. 
Behrend, F. 1918. Die Stratigraphie des ostlichen Zentralafrika unter Beriicksichtigung der 

Beziehungen zu Siidafrika. Beitr. geol. Erforsch. dtsch. SchGeb., Berlin, 15 : 1-148. 
Benecke, E. W. 1905. Die Versteinerungen der Eisenerzformation von Deutsch-Lothringen 

und Luxemburg. Abh. geol. Specialk. Els.-Loth., Strasburg (N.F.) 6 : 1-598, pis. 1-59. 
Besairie, H. 1936. Fossiles du Bathonien moyen. Mdm. Acad, malgache, Antananarivo, 

21 : 120-122, pi. 7. 
Beyrich, H. E. 1877. Uber jurassische Ammoniten von Mombassa. Mber. preuss. Akad. 

Wiss., Berlin, 1877 : 96-103. 
■ 1878. Uber Hildebrandt's geologische Sammlungen von Mombassa. Mber. preuss. 

Akad. Wiss., Berlin, 1878 : 767-775. 
Bigot, A. & Matte. 1903-04. Catalogue critique de la collection Defrance conservee 

au Mus6e d'Histoire Naturelle de Caen. Premiere partie : pelecypodes. Bull. Soc. linn. 

Normandie, Caen (5) 6 : 152-185 ; (5) 7 : 243-268. 
Blake, J. F. 1905-07. A monograph of the fauna of the Cornbrash. 102 pp., 9 pis. 

Palaeontogr. Soc. [Monogr.], London. 
Blanford, W. T. 1870. Observations on the geology and zoology of Abyssinia, xii + 487 

pp., 16 pis. London. 
Blaschke, F. 1911. Zur Tithonfauna von Stramberg in Mahren. Ann. naturh. Hofmus., 

Wien, 25 : 143-222, pis. 1-6. 
Boden, K. 191 1. Die Fauna des unteren Oxford von Popilany in Litauen. Geol. paldont- 

Abh., Jena (N.F.) 10 : 125-199, pis. 20-27. 
Boehm, G. 1881. Die Fauna des Kelheimer Diceras-Kalkes. Zweite Abtheilung : Bivalven. 

Palaeontogr aphica, Cassel, 28 : 141-191, pis. 23-40. 
1883. Die Bivalven der Stramberger Schichten. Palaeontogr aphica, Cassel, Suppl. 4 : 

485-680, atlas, pis. 53-70. 
Boehm, J. 1901. Ueber die Fauna der Pereiros-Schichten. Z. dtsch. geol. Ges., Berlin, 

53 : 211-252, pis. 8-10. 
Borissiak, A. 1905. Die Pelecypoden der Jura-Ablagerungen im europaeischen Russland. 

II. Arcidae. M6m. Com. geol., St. Pelersb. (n.s.) 19 : 1-63, pis. 1-4. 
Bouillerie, S. M. G. de la. 1921. Guide paUontologique pour les terrains de la Sarthe. Faune 

de Pared et de Dureil. PiUcypodes (Bathonien supirieur, Callovien infSrieur). 44 pp., 

5 pis. Le Mans. 
Brauns, D. 1869. Der mittlere Jura im nordwestlichen Deutschland. vi + 314 PP-. 2 pis- 

Cassel. 

1871. Der untere Jura im nordwestlichen Deutschland. x + 494 PP-> 2 pis. Braunschweig. 

1874. Der obere Jura im nordwestlichen Deutschland. x + 434 pp., 3 pis. Braunschweig, 



FROM TANGANYIKA AND KENYA 199 

Brongniart, A. 1821. Sur les caracteres geologiques des formations. Ann. Min., Paris, 

6 : 537-572, pis. 7- 8. 
Bronn, H. G. 1836. tlbersicht und Abbildungen der bis jetzt bekannten Nerinea-Arten. 

Neues Jb. Min. Geol. Palaont., Stuttgart, 1836 : 544-566, pi. 6. 
Brosamlen, R. 1909. Beitrag zur Kenntnis der Gastropoden des schwabischen Jura. 

Palaeontographica, Stuttgart, 56 : 177-321, pis. 17-22. 
Buvignier, A. 1852. Statistique giologique, miniralogique, miner allurgique et paUontologique 

du dipartement de la Meuse. Atlas, 52 pp., 32 pis. Paris. 
Casey, R. 1952. Some genera and subgenera, mainly new, of Mesozoic heterodont lamelli- 

branchs. Proc. malac. Soc. Lond., 29 : 121-176, pis. 7-9. 
1961. The stratigraphical palaeontology of the Lower Greensand. Palaeontology, 

London, 3 : 487-621, pis. 77-84. 
Caswell, P. V. 1953. Geology of the Mombasa-Kwale area. Rep. geol. Surv. Kenya, 

Nairobi, 24. 68 pp., 8 maps. 
1956. Geology of the Kilifi-Mazeras area. Rep. geol. Surv. Kenya, Nairobi, 34. 54 pp., 

1 map. 
Chapuis, F. & Dewalque, G. 1853. Description des fossiles des terrains secondaires de la 

province de Luxembourg. Mini. Acad. R. Belg., Bruxelles, 25 : 1-303, pis. 1-38. 
Chavan, A. 1952. Les pelecypodes des sables astartiens de Cordebugle (Calvados). Abh. 

schweiz. palaont. Ges., Basel, 69 : 1-132, pis. 1-4. 
Choffat, P. 1893. Description de la faune jurassique de Portugal. Mollusques lamelli- 

branches. Ordre Siphonida. M6m. Comm. giol. Portugal, Lisbon. 39 pp., 9 pis. 
Contejean, C. i860. Etude de l'etage kimmeridien dans les environs de Montbeliard. 

Mim. Soc. Emul. Doubs, Besancon (3) 4 : 1-352, pis. 1-27. 
Cossmann, M. 1885. Contribution a l'etude de la faune de l'etage bathonien en France 

(Gastropodes) . Mim. Soc. giol. Fr., Paris (3) 3, 3 : 1-374, pl s - 1-18. 

1895a. Essais de paUoconchologie comparee, 1. 159 pp., 7 pis. Paris. 

18956-18966. Contribution a la paleontologie francaise des terrains jurassiques. Mim. 

Soc. giol. Fr. Paliont., Paris, 14 : 1-167, pis. 1-6. 
1898. Contribution a la paleontologie francaise des terrains jurassiques. Gastropodes : 

Nerinees. Mim. Soc. giol. Fr. Paliont., Paris, 19 : 1-179, pis. 1-13. 

1899. Rectifications de nomenclature. Rev. crit. Paliozool., Paris, 3 : 133—139. 

1900. Note sur les gastropodes du gisement bathonien de Saint-Gaultier (Indre). Bull. 

Soc. geol. Fr., Paris (3) 27 : 543-585. pis- W-*7- 
1902. Paleontologie. In Chartron, C. & Cossmann, M., Note sur lTnfralias de la Vendee 

et specialement sur un gisement situe dans la commune du Simon-la- Vineuse. Bull. Soc. 

giol. Fr., Paris (4) 2 : 163-203, pis. 3, 4. 
1906. Description de quelques pelecypodes jurassiques de France. Premier article. 

C.R. Ass. franc. Av. Sci., Paris, Congr. 1905 : 284-297, pis. 1, 2. 
1907a. Paleontologie. In Thiery, P. & Cossmann, M., Note sur le Callovien de la Haute- 

Marne. Bull. Soc. Agric. Hte-Saone, Vesoul, 1907 : 69-147, pis. 1-3. 
19076. Troisieme note sur le Bathonien de Saint-Gaultier (Indre). Bull. Soc. giol. Fr., 

Paris (4) 7 : 224-253, pis. 7, 8. 

1909. Essais de paUoconchologie comparie, 8. 248 pp., 4 pis. Paris. 

1912. Quelques pelecypodes jurassiques recueillis en France. 4e article. Mim. hors 

vol., Ass. f rang. Av. Sci., Paris. 10 pp., 2 pis. 
1913a. Quelques pelecypodes jurassiques recueillis en France. 5e article. Mim. hors 

vol., Ass. franc. Av. Sci., Paris, n pp., 3 pis. 
19136. Contribution a la paleontologie francaise des terrains jurassiques. III. Cerithi- 

acea et Loxonematacea. Mim. Soc. giol. Fr. Paliont., Paris, 46. 268 pp., 18 pis. 
1915a- Description de quelques pelecypodes jurassiques recueillis en France. 6e article. 

Mim. hors vol., Ass. franc. Av. Sci., Paris. 48 pp., pis. 4-9. 
191 56. Description de quelques pelecypodes du Bradfordien et du Callovien de Pougues- 



zoo JURASSIC BIVALVIA AND GASTROPODA 

les-Eaux (Nievre). Bull. Soc. nivern. Lett. Sci., Nevers, 15 : 1-15, pis. 1-3. 

1921. Description de pelecypodes jurassiques recueillis en France. He ser., ie article. 

Mini, hors vol., Ass. fran$. Av. Sci., Paris. 29 pp., 4 pis. 

1923. Description de pelecypodes jurassiques recueillis en France. He ser., 2e article. 

Mim. hors vol., Ass. franc. Av. Sci., Paris. 21 pp., pis. 5, 6. 

1924. Extension dans les Deux-Sevres de la faune du Callovien de Montreuil-Bellay. 

Mim. Soc. giol. Breiagne, Rennes, 1 : 1-53, pis. 1-7. 

1925. Sur quelques pelecypodes du jurassique francais. Bull. Soc. giol. Fr., Paris (4) 

24 : 654-671, pis. 21, 22. 

1926. Description des fossiles. In Douville, H., Le Callovien dans le massif du Moghara. 

Bull. Soc. giol. Fr., Paris (4) 25 : 305-326, pis. 5-8. 

Cottreau, J. 1925-32. Types du Prodrome de paleontologie stratigraphique universelle de 

d'Orbigny, 2. Ann. Paliont., Paris, 14-21. 222 pp., pis. 37-68. 
Couffon, O. 1917-19. Le Callovien du Chalet, Commune de Montreuil-Bellay (M.-&-L.). 

Bull. Soc. Etudes sci. Angers, 47 : 65-130 ; 48 : 235-321 ; 49 : 15-97, Atlas, 18 pis. 
Cox, L. R. 1925. The fauna of the basal shell-bed of the Portland Stone, Isle of Portland. 

Proc. Dorset nat. Hist. Fid CI., Dorchester, 46 : 1 13-172, pis. 1-5. 
1929. A synopsis of the Lamellibranchia and Gastropoda of the Portland Beds of 

England. Part I. — Lamellibranchia. Proc. Dorset nat. Hist. Fid CI., Dorchester, 50 : 

131-202, pis. 1-6. 
J 935 a - Jurassic Gastropoda and Lamellibranchia. In Macfadyen, W. A. & others. 

The Mesozoic palaeontology of British Somaliland : 148-197, pis. 14-21. London. 

19356. The Triassic, Jurassic and Cretaceous Gastropoda and Lamellibranchia of the 

Attock district (Punjab). Palaeont. indica, Calcutta (n.s.) 20, 5 : 1-27, pis. 1, 2. 

1936. The Gastropoda and Lamellibranchia of the Green Ammonite Beds of Dorset. 

Quart. J. geol. Soc. Lond., 92 : 456-471, pi. 34. 

I937 a - Notes on Jurassic Lamellibranchia. II. On Indogrammatodon, a new subgenus 

from the Jurassic of the Indo-African province. Proc. malac. Soc. Lond., 22 : 194-198, 
pis. 15, 16. 

I 937&- Notes on Jurassic Lamellibranchia. III. On a new Trigonia and other species 

from Tanganyika Territory. Proc. malac. Soc. Lond., 22 : 198-203, pi. 16. 

1937c. Notes on Jurassic Lamellibranchia. V. On a new subgenus of Mytilus and a 

new Mytilus-like genus. Proc. malac. Soc. Lond., 22 : 339-348, pi. 17. 

1938. Change in name of the Jurassic gastropod Bourguelia striata (J. Sowerby). Proc. 

malac. Soc. Lond., 23 : 59-60. 

1940. The Jurassic lamellibranch fauna of Kuchh (Cutch). Palaeont. indica, Calcutta 

(9) 3, 3 : i-i57> P ls - J- 10 - 

1943- The English Upper Lias and Inferior Oolite species of Lima. Proc. malac. Soc. 

Lond., 25 : 151-187, pis. 6-29. 

1944a. On Pseudolimea Arkell. Proc. malac. Soc. Lond., 26 : 74-88, pis. 2, 3. 

19446- On the Jurassic lamellibranch genera Hartwellia and Pronoella. Geol. Mag., 

Lond., 81 : 100-112. 

1947. The lamellibranch family Cyprinidae in the Lower Oolites of England. Proc. 

malac. Soc. Lond., 27 : 141-184, pis. 8-10. 

1952. The Jurassic lamellibranch fauna of Cutch (Kachh). No. 3, Families Pectinidae, 

Amusiidae, Plicatulidae, Limidae, Ostreidae and Trigoniidae (supplement). Palaeont. 
indica, Calcutta (9) 3, 4 : 1-128, pis. 1-12. 

1954- Notes relating to the taxonomy of the gastropod superfamily Nerineacea. Proc. 

malac. Soc. Lond., 31 : 12-16. 

i960. Contributions to systematic descriptions. In Treatise on Invertebrate Paleontology 

(edit. Moore, R. C), vol. I. Lawrence, Kansas. 

Cox, L. R. & Arkell, W. J. 1948-50. A survey of the Mollusca of the British Great Oolite 
Series, xxiv -f 105 pp. Palaeontogr. Soc. [Monogr.], London. 



FROM TANGANYIKA AND KENYA 201 

Credner, H. 1863. Uebev die Gliederung der oberen J uraformation und dev W ealden-Bildung 

im nordwestlichen Deutschland. xii + 192 pp., 11 pis. Prag. 
Dacque, E. 1905. Beitrage zur Geologie des Somalilandes. Zweiter Teil : Oberer Jura. 

Beitr. Paldont. Geol. Ost.-Ung., Wien & Leipzig, 17 : 119-159, pis. 14-18. 

1910. Dogger und Malm aus Ostafrika. Beitr. Paldont. Geol. Ost.-Ung., Wien & Leipzig, 

23 : 1-62, pis. 1-6. 

Dacque, E. & Krenkel, E. 1909. Jura und Kreide in Ostafrika. N. Jb. Min. Geol. Paldont., 

Stuttgart, Beil.-Bd., 28 : 150-232. 
Dechaseaux, C. 1936. Pectinides jurassiques de Test du Bassin de Paris. Ann. PaUont., 

Paris, 25 : 1-148, pis. 1-10. 
Defrance, A. 1821. Article, " Huitres ". Diet. Sci. nat., Paris, 22 : 20-33. 

1822. Article, " Isocarde ". Diet. Sci. nat., Paris, 24 : 17-18. 

Dietrich, W. O. 1914. Die Gastropoden der Tendaguruschichten, der Aptstufe und der 

Oberkreide im sudlichen Deutsch-Ostafrika. Arch. Biontol., Berl., 3, 4 : 97-153, pis. n-13. 
■ 1925. Uber eine dem mittleren Sauriermergel am Tendaguru aquivalente, rein marine 

Kimmeridgebildung in Mahokondo, Deutsch-Ostafrika. Palaeontographica, Stuttgart, 

Suppl. 7 (2) 1 : 1-23, pis. 1-3. 
1927. Das Alter der Trigonienschichten am Tendaguru. Zbl. Min. Geol. Paldont., 

Stuttgart, 1927, B : 59-64- 

1933- Zur Stratigraphie und Palaeontologie der Tendaguruschichten. Palaeontographica, 

Stuttgart, Suppl. 7 (2) 2 : 1-86, pis. 1-12. 

Dixey, F. 1948. Geology of northern Kenya. Rep. geol. Surv. Kenya, Nairobi, 15. 43 pp., 

4 pis. 
Dollfus, A. 1863. Protogea Gallica. La faune kimme'ridienne du Cap de la Heve. vii + 

102 pp., 18 pis. Paris. 
Douglas, J. A. & Arkell, W. J. 1932. The stratigraphical distribution of the Cornbrash. 

II. The North-Eastern area. Quart. J. geol. Soc. Lond., 88 : 1 12-170, pis. 10-12. 
Douville, H. 1886. Examen des fossiles rapportes du Choa par M. Aubry. Bull. Soc. g&ol. 

Fr., Paris (3) 14 : 223-241, pi. 12. 

1907a. Etudes sur les lamellibranch.es. Vulsellides. Ann. Paldont., Paris, 2 : 97-118, 

pis. 15, 16. 

19076. Les lamellibranches cavicoles ou Desmodontes. Bull. Soc. gdol. Fr., Paris (4) 

7 : 96-114, pi. 2. 

1913- Classification des lamellibranches. Bull. Soc. giol. Fr., Paris (4) 12 : 419-467. 

1916. Les terrains secondaires dans le massif du Moghara a Test de l'isthme de Suez. 

Paleontologie. Mim. Acad. Sci., Paris (2) 54 : 1-184, pis. 1-21. 

Dubar, G. 1948. La faune domerienne du Jebel Bou-Dahar. Notes Serv. Min. Maroc, 

Lille, 68. 250 pp., 30 pis. 
Dumortier, E. 1874. Etudes paliontologiques sur les depots jurassiques du bassin du Rhone. 

Quatrieme partie. Lias superieur. 337 pp., 62 pis. Paris. 
Ernst, W. 1923. Zur Stratigraphie und Fauna des Lias £ im nordwestlichen Deutschland. 

Erster Teil. Palaeontographica, Stuttgart, 65 : 1-95, pis. 1-6. 
Eudes-Deslongchamps, J. A. 1824. Memoire sur les coquilles du genre Gervillia. Mem. 

Soc. linn. Normandie, Caen, 1 : 1 16-134, P^ s - I_ 5- 
Fabiani, R. & Ruiz, C. 1933. Giacitura e fauna dei tufi vulcanici giuresi di Roccapalumba 

(Palermo). Mem. Soc. geol. ital., Roma, 1 : 1-52, pis. 1, 2. 
Farler, J. P. 1879. The Usambara country in East Africa. Geogr. J., London (n.s.) 1 : 

81-97. 
Favre, J. 191 2-1 8. Polypes ; Annelides ; Conchiferes ; Rudistes ; Gasteropodes ; Tra- 

chelipodes ; Cephalopodes. In Clerc, M. & Favre, J. Catalogue illustre de la Collection 

Lamarck, livr. 2-6. Geneve. 
Fischer, H. 1908. Notes sur quelques coquilles fossiles des terrains jurassiques. J. Conchy I., 

Paris, 56 : 256-270, pis. 9-1 1. 



202 JURASSIC BIVALVIA AND GASTROPODA 

Fischer, J. C. 1953. Note sur les gasteropodes d'un nouveau gite coquillier du Bathonien des 

Ardennes. /. Conchyl., Paris, 93 : 3-25, pis. 1, 2. 
Flamand, G. B. M. 191 1. Recherches geologiques et geographiques sur le Haut-Pays de 

l'Oranie et sur le Sahara (Algerie et Territoires du Sud). Serv. giol. Algdrie, Lyon. 1001 pp., 

16 pis. 
Fraas, E. 1908a. Ostafrikanische Dinosaurier. Palaeontographica, Stuttgart, 55 : 105-144, 

pis. 8-12. 

19086. Beobachtungen iiber den ostafrikanischen Jura (mit Fossilnotizen von E. Dacque). 

Zbl. Min. Geol. Paldont., Stuttgart, 1908 : 641-651. 

Fraas, O. 1859. Jurassisches Vorkommen auf der Ostkiiste von Afrika. Jh. Ver. vaterl. 

Naturk. Wiirttemb., Stuttgart, 15 : 356-357. 
Futterer, K. 1894. Beitrage zur Kenntniss des Jura in Ost-Afrika. Z. dtsch. geol. Ges., 

Berlin, 46 : 1-49, pis. 1-6. 

1897. Beitrage zur Kenntniss des Jura in Ost-Afrika. IV. Der Jura von Schoa (Siid- 

Abessinien). Z. dtsch. geol. Ges., Berlin, 49 : 568-627, pis. 19-22. 

Gemmellaro, G. G. 1869. Molluschi Gasteropodi. Studj paleontologici sulla fauna del 

calcario a Terebratula janitor del nord di Sicilia, 2. 92 pp., 15 pis. Palermo. 
Gerber, E. 191 8. Beitrage zur Kenntnis der Gattungen Ceromya und Ceromyopsis. Abh. 

schweiz. paldont. Ges., Genf, 43 : 1-24, pi. 1. 
Gillieron, V. 1886. La faune des Couches a Mytilus consideree comme phase meconnue de 

la transformation de formes animales. Verh. naturf. Ges. Basel, 8 : 133-164. 
Goldfuss, G. A. 1826-44. Petrefacta Germaniae, 1-3. Duesseldorf. (1, 1826-33 '< 2, 

1833-40 ; 3, 1844) 
Gras, A. 1852. Catalogue des corps organises fossiles qui se rencontrent dans le dipartement de 

V I sere. 54 pp., 4 pis. Grenoble. 
Gregory, J. W. 1927. Further Jurassic fossils from Kenya Colony. Geol. Mag., Lond., 

64 : 325. 
Greppin, E. 1898-1900. Description des fossiles du Bajocien superieur des environs de 

Bale. Abh. schweiz. paldont. Ges., Genf, 25 : 1-52, pis. 1-5 ; 26 : 53-126, pis. 6-12 ; 

27 : 127-210, pis. 13-19. 
Greppin, J. B. 1870. Description geologique du Jura bernois et de quelques districts 

adjacents. Beitr. geol. Karte Schweiz, Bern, 8 : 1-357, pis. 1-7. 
Guillaume, L. 1928. Revision des posidonomyes jurassiques. Bull. Soc. giol. Fr., Paris 

(4) 27 : 217-234, pi. 10. 
Haber, G. 1932-34. Gastropoda, Amphineuraet Scaphopoda jurassica. Fossilium Catalogus. 

1 : Animalia, Berlin, 53, 65. 400 pp. (not completed). 
Hennig, E. 1914a. Beitrage zur Geologie und Stratigraphie Deutsch-Ostafrikas. II. 

Geologisch-stratigraphische Beobachtungen im Gebiete der Jura-Ablagerungen an der 

Deutsch-Ostafrikanischen Zentralbahn. Arch. Biontol., Berl., 3, 3 : 53-72. 

19146. Die Invertebraten-Fauna der Saurierschichten am Tendaguru. Arch. Biontol., 

Berl., 3, 4 : 154-185, pi. 14. 

1917. Die geologischen Verhaltnisse des Pindiro-Tals im sudlichen Deutsch-Ostafrika. 

Z. dtsch. geol. Ges., Berlin, 68, Monatsber. : 181-200. 
1924. Der mittlere Jura im Hinterlande von Daressalaam (Deutsch-Ostafrika). Monogr. 

Geol. Paldont., Leipzig (2) 2 : 1-131, pis. 1-4. 
1927. Die Altersfragen der Tendaguru -Schich ten im sudlichen Deutsch-Ostafrika. Zbl. 

Min. Geol. Paldont., Stuttgart, 1927, B : 64-69. 

1937- Der Sedimentstreifen des Lindi-Kilwa-Hinterlandes (Deutsch-Ostafrika). Palae- 
ontographica. Stuttgart, Suppl. 7, 2 Reihe, Teil 2, Lief. 2 : 99-186, pis. 13-15. 

Hildebrandt, J. M. 1879. Von Mombasa nach Kitui. Z. Ges. Erdk. Berl., 14 : 241-278. 
Holdhaus, K. 1913. Fauna of the Spiti Shales (Lamellibranchiata and Gastropoda). 
Palaeont. indica, Calcutta (9) 4, 2 : 397-456, pis. 94-100. 



FROM TANGANYIKA AND KENYA 203 

Hudleston, W. H. 1882-85. Contributions to the palaeontology of the Yorkshire Oolites. 

No. 2. Gasteropoda of the Oxfordian and Lower Oolites. Geol. Mag., Lond. (2) 9 : 

145-151 ; 193-205, pi. 5 ; 241-251, pi. 6 (1882) ; (3) 1 : 49-63, pi. 3 ; 107-115, pi. 4 ; 

146-154, pi. 6 ; 193-204, pi. 7 ; 241-252, pi. 8 ; 293-303, pi. 9 (1884) ; (3) 2 : 49-59, 

pi. 2 ; 121-129, pi. 3 ; 151-159, pi. 4 ; 201-207, pi. 5 ; 252-257 (1885). 
1887-96. A monograph of the Inferior Oolite Gasteropoda. 514 pp., 44 pis. Palae- 

ontogr. Soc. [Monogr.], London. 
Jaekel, O. 1893. Uber oberjurassische Fossilien aus Usambara. Z. dtsch. geol. Ges., Berlin, 

45 : 507-508. 
Jekelius, E. 1916. A brassoi hegyek mezozoos faunaja. III-VII. A brassoi Dogger- 6s 

Malmfauna. Magyar foldt. Intizet Evkon., Budapest, 24 : 220-314, pis. 4-6. 
Joubert, P. i960. Geology of the Mandera-Damassa area. Rep. geol. Surv. Kenya, Nairobi, 

48 : 1-65, pis. 1-12. 
King, A. J. 1954. Notes on the Jurassic rocks of part of the Morogoro and Bagamoyo 

districts. Rec. geol. Surv. Tanganyika, Dar es Salaam, 1 : 15-19. 
Kitchin, F. L. 1903. The Jurassic fauna of Cutch, 3 (2) : the Lamellibranchiata. No. 1, 

genus Trigonia. Palaeont. indica, Calcutta (9) 3, 2 : 1-122, pis. 1-10. 

1926. The so-called Malone Jurassic formation in Texas. Geol. Mag., Lond., 63 : 454-469. 

1929. On the age of the Middle and Upper Deinosaur Deposits at Tendaguru, Tanganyika 

Territory. Geol. Mag., Lond., 66 : 193-220. 
Koch, F. C. L. & Dunker, W. 1837. Beitrdge zur Kenntniss des norddeutschen Oolithgebildes 

und dessen Versteinerungen. 64 pp., 7 pis. Braunschweig. 
Koert, W. 1904. Notiz iiber die Auffinding von Kelloway bei Tanga (Deutsch-Ostafrika). 

Z. dtsch. geol. Ges., Berlin, 56 (briefl. Mitt.) : 150-153. 
Krenkel, E. 1910. Die untere Kreide von Deutsch-Ostafrika. Beitr. Palaont. Geol. Ost.- 

Ung., Wien & Leipzig, 23 : 201-250, pis. 20-23. 
1925. Geologie Afrikas. Erster Teil. In Geologie der Erde, ed. E. Krenkel. 461 pp. 

Berlin. 
Krumbeck, L. 1905. Die Brachiopoden- und Molluskenfauna des Glandarienkalkes. Beitr. 

Palaont. Geol. Osl.-Ung., Wien & Leipzig, 18 : 65-162, pis. 8-14. 
Kuhn, O. 1935. Revision der Opalinuston- (Dogger a) Fauna in Franken, mit Ausschluss 

der Cephalopoden. Palaont. Z., Berlin, 17 : 109-158, pis. 8-10. 
1938. Die Fauna des Dogger 8 der Frankenalb. Nova Acta Leopoldina, Halle (N.F.) 

6 : 125-170, pis. 19-24. 
Lahusen, I. 1883. Die Fauna der jurassischen Bildungen des Rjasanschen Gouvernements. 

Mdm. Com. giol., St. PStersb., 1, 1 : 1-94, pis. 1-11. 
Lange, E. 1914. Die Brachiopoden, Lamellibranchiaten und Anneliden der Trigonia 

Schwarzi-Schicht, nebst vergleichender Ubersicht der Trigonien der gesamten Tendaguru- 

schichten. Arch. Biontol., Berl., 3, 4 : 187-289, pis. 14-22. 
Lange, E. 1917. Trigonia smeei Sowerby und ihre horizontale Verbreitung. Zbl. Min. Geol. 

Palaont., Stuttgart, 1917 : 492-496. 
Lanquine, A. 1929. Le Lias et le Jurassique des chaines provencales. Recherches strati- 

graphiques et paleontologiques. I. Le Lias et le Jurassique inferieur. Bull. Carte gSol. 

Fr., Paris, 32 (173). 385 pp., 12 pis. 
Laube, G. C. 1867. Die Bivalven des Braunen Jura von Balin. Denkschr. Akad. Wiss. 

Wien, 27, 2 : 11-61, pis. 1-5. 
Lebkuchner, R. 1932. Die Trigonien des siiddeutschen Jura. Palaeontographica, Stuttgart, 

77 : 1-119, pis. 1-16. 
Lemoine, P. 1906. Etudes geologiques dans le nord de Madagascar. Ann. Hdbert, Paris, 3. 

520 pp., 4 pis. 

1910. [Description of gastropod types.] Palaeont. univ., Centuria, 2 (3) 1. 

Lennier, G. 1872. Etudes giologiques et paleontologiques sur V embouchure de la Seine et les 

falaises de la Haute-Normandie. xvi + 245 pp., 12 pis. Havre. 



2o 4 JURASSIC BIVALVIA AND GASTROPODA 

Lissajous, M. 1912. Jurassique maconnais. Fossiles caracteristiqu.es. 208 pp., atlas, 19 pis. 
Macon. 

1923. Etude sur la faune du Bathonien des environs de Macon. Trav. Lab. GSol. Univ. 

Lyon, Mini., 3. 286 pp., 33 pis. 

Loriol, P. de. 1867a. Description des fossiles de l'oolite corallienne, de l'etage valangien, et 
de l'etage urgonien du Mont Saleve. In Favre, J. A., Recherches giologiques dans les parties 
de la Savoie, duPidmont, et de la Suisse voisines du Mont Blanc, Paris & Geneve, 1 : 310-405, 
pis. A-C of atlas. 

18676. Description des fossiles. In Loriol, P. de & Pellat, E., Monographic paleonto- 

logique et geologique de l'etage portlandien des environs de Boulogne-sur-Mer. Mint. 
Soc. Phys. Geneve, 19 : 5-135, pis. 1-11. 

1868. Description des fossiles. In Loriol, P. de & Cotteau, G., Monographic paleonto- 

logique et geologique de l'etage portlandien du departement de l'Yonne. Bull. Soc. Sci. 
hist. nat. Yonne, Auxerre, 21 : 441-675, pis. 2-15. 

- 1872. Description des fossiles. In Loriol, P. de, Royer, E., & Tombeck, H., Monographic 
paleontologique et geologique des etages superieurs de la formation jurassique du departe- 
ment de la Haute-Marne. Mini. Soc. linn. Normandie, Caen, 16 : 1-484, pis. 1-26. 

1874-75. Description des fossiles. In Loriol, P. de & Pellat, E., Monographic paleonto- 
logique et geologique des etages superieurs de la formation jurassique des environs de 
Boulogne-sur-Mer. Mim. Soc. Phys. Geneve, 23 : 261-407, pis. 1-10 ; 24 : 1-326, 
pis. 11-26. 

1876-78. Monographie paleontologique des couches de la Zone a Ammonites tenuilobatus 

(Badener Schichten) de Baden (Argovie). Abh. schweiz. palaont. Ges., Genf, 3 : 1-32, 
pis. 1-4 ; 4 : 33-76, pis. 5-12 ; 5 : 77-200, pis. 13-23. 

1 88 1. Monographie paleontologique des couches de la Zone a Ammonites tenuilobatus 

(Badener Schichten) d'Oberbuchsitten et de Wangen (Soleure). Abh. schweiz. palaont. Ges., 
Genf, 7 : 1-60, pis. A, 1-10 ; 8 : 61-120, pis. 11-14. 

1883. Paleontologie. In Loriol, P. de & Schardt, H., Etude paleontologique et strati- 

graphique des Couches a Mytilus des Alpes vaudoises. Abh. schweiz. palaont. Ges., Genf, 
10 : 1-96, pis. 1-12. 

1886-88. Etude sur les mollusques des couches coralligenes de Valfin (Jura). Abh. 

schweiz. palaont. Ges., Genf, 13 : 1-120, pis. A-C, 1-11 ; 14 : 121-224, P^ s - I2_2 3 > 15 : 
225-369, pis. 24-37. 

1889-93. Etudes sur les mollusques des couches coralligenes inferieures du Jura bernois. 

Abh. schweiz. palaont. Ges., Genf, 16 : 1-79, pis. 1-9 ; 17 : 81-174, pl s - 10-18 ; 18 : 175-258, 
pis. 19-27 ; 19 : 261-419, pis. 28-36. 

1894a. Description des mollusques et brachiopodes des couches sequaniennes de Tonnerre 

(Yonne). Abh. schweiz. palaont. Ges., Genf, 20 : 1-213, pis. 1-11. 

18946. Etude sur les mollusques du Rauracien inferieur du Jura bernois. Abh. schweiz. 

palaont. Ges., Genf, 21 : 1-100, pis. 1-10. 

1895. Etude sur les mollusques du Rauracien superieur du Jura bernois. Premier 

supplement. Abh. schweiz. palaont. Ges., Genf, 22 : 1-5 1, pis. 1-10. 

1896-97. Etude sur les mollusques et brachipodes de l'Oxfordien superieur et moyen du 

Jura bernois. Abh. schweiz. palaont. Ges., Genf, 23 : 1-77, pis. 1-11 ; 24 : 78-158, pis. 
12-17. 

1898-99. Etude sur les mollusques et brachiopodes de l'Oxfordien inferieur ou Zone a 

Ammonites renggeri du Jura bernois. Abh. schweiz. palaont. Ges., Genf, 25 : 1-116, pis. 
1-7 ; 26 : 117-187, pis. 8-10. 

1900. Etude sur les mollusques et brachiopodes de l'Oxfordien inferieur ou Zone a 

Ammonites renggeri du Jura l^donien. Abh. schweiz. palaont. Ges., Genf, 27 : 1-143, 
pis. 1-6. 

1901. Etude sur les mollusques et brachiopodes de l'Oxfordien superieur et moyen du 



FROM TANGANYIKA AND KENYA 205 

Jura bernois. Premier Supplement. Abh. schweiz. paldont. Ges., Genf, 28 : 1-119, 
pis. 1-7. 

1902-04. Etude sur les mollusques et brachiopodes de l'Oxfordien superieur et moyen du 

Jura ledonien. Abh. schweiz. paldont. Ges., Genf, 29 : 1-76, pis. 1-5 ; 30 : 77-160, pis. 
6-19 ; 31 : 161-290, pis. 20-27. 

Lycett, J. 1850. Tabular view of fossil shells from the middle division of the Inferior Oolite 
in Gloucestershire. Ann. Mag. nat. Hist., London (2) 6 : 401-425, pi. 11. 

1863. Supplementary monograph on the Mollusca from the Stonesfield Slate, Great 

Oolite, Forest Marble, and Cornbrash. 129 pp., pis. 31-45. Palaeontogr. Soc. [Monogr.], 
London. 

1872-83. A monograph of the British fossil Trigoniae. 245 pp., 41 pis. & Suppl. 19 pp., 

4 pis. Palaeontogr. Soc. [Monogr.], London. 
Martin, J. 1863. Note sur quelques fossiles nouveaux ou peu connus de l'etage bathonien 

de la Cote-d'Or. MSm. Acad. Dijon (2) 10 : 55-69, pis. 1-6. 
Mayer, C. 1875. Description de coquilles fossiles des terrains jurassiques. /. Conchyl., 

Paris, 23 : 232-241, pi. 10. 
McDonald, A. I. & Trueman, A. E. 1921. The evolution of certain Liassic gastropods, with 

special reference to their use in stratigraphy. Quart. J. geol. Soc. Lond., 77 : 297-343, 

pi. 22. 
Menzel, H. 1902. Neue Funde von Jura-Fossilien in Deutsch-Ostalrika. Mitt, dtsch. 

Schutzgeb., Berlin, 15 : 41-46. 
Moesch, C. 1867. Geologische Beschreibung des Aargauer-Jura und der nordlichen Gebiete 

des Kantons Zurich. Beitr. geol. Karte Schweiz, Bern, 4. 319 + xv pp., 7 + 3 pis. 

1874-75. Monographic der Pholadomyen. Abh. schweiz. paldont. Ges., Genf, 1 : 1-78, 

pis. 1-29 ; 2 : 79-135, pis. 30-40. 

Moore, C. 1867. On the Middle and Upper Lias of the South West of England. Proc. 

Somerselsh. archaeol. nat. Hist. Soc, Taunton, 13 : 119-244, pis. 1-7. 
Morris, J. & Lycett, J. 1851-55. A monograph of the Mollusca from the Great Oolite. 

viii -f- 130 -j- 147 pp., 15 + 15 pis. Palaeontogr. Soc. [Monogr.], London. 
Muller, G. 1900. Versteinerungen des Jura und der Kreide. Deutsch-Ost-Afrika, Berlin, 

7 : 5M-577. Pis. 14-25- 
Munier-Chalmas, E. 1882. Revue critique de quelques especes du genre Trigonia. Bull. 

Soc. gdol. Fr., Paris (3) 10 : 494-504, pi. 12. 
Neumayr, M. 1873. Die Fauna der Schichten mit Aspidoceras acanthicum. Abh. geol. 

Reichsanst. Wien, 5 : 141-257, pis. 31-42. 
1885. Die geographische Verbreitung der Juraformation. Denkschr. Akad. Wiss. Wien, 

50 : 57-142. 
Newton, R. B. 1889. Notes on fossils from Madagascar, with descriptions of two new species 

of Jurassic Pelecypoda from that island. Quart. J . geol. Soc. Lond., 45 : 331-338, pi. 14. 

1895. On a collection of fossils from Madagascar obtained by the Rev. R. Baron. Quart. 

J. geol. Soc. Lond., 51 : 72-91, pis. 2, 3. 

Oppel, A. 1856-58. Die Juraformation Englands, Frankreichs und des siidwestlichen 
Deutschlands, nach ihren einzelnen Gliedern eingetheilt und verglichen. Jh. Ver. vaterl. 
Naturk. Wiirttemb., Stuttgart, 12 : 121-312, 313-558 ; 13 : 141-396 ; 14 : 129-291. 

1863-65. Ueber ostindische Fossilreste aus den secundaren Ablagerungen von Spiti und 

Gnari-Khorsum in Tibet. Palaeont. Mitt., Stuttgart, 4 : 267-322, pis. 75-88. 

Orbigny, A. d' 1822. Notice sur quelques especes nouvelles de mollusques fossiles, du 
departement de la Charente-inferieure. Mem. Mus. Hist, nat., Paris, 8 : 98-110, pis. 6-8. 

1850a, b. Prodrome de paUontologie stratigraphique universelle des animaux mollusques et 

rayonnes, 1. 394 pp. ; 2. 428 pp. Paris. 

1851-60. Gasteropodes. PaUontologie fran^aise, terrains jurassiques, Paris, 2. 623 pp., 

pis. 235-428. 

Parkinson, J. 181 1. Organic remains of a former world, 3. xv -|- 479 pp., 22 pis. London. 



206 JURASSIC BIVALVIA AND GASTROPODA 

Parsons, E. 1929. The origin of the Great Rift Valleys as evidenced by the geology of 

Kenya Colony. Trans, geol. Soc. S. Afr., Johannesburg, 31 : 63-96. 
Pchelintsev, V. 193 1. Materials for the study of the Upper Jurassic deposits of the 

Caucasus. Trans, geol. prosp. Serv. U.S.S.R., Moscow & Leningrad, 91 : 1-170, pis. 1-8. 
Peron, A. 1906. Etudes paleontologiques sur les terrains du departement de l'Yonne. Les 

pelecypodes rauraciens et sequaniens. Bull. Soc. Sci. hist. nat. Yonne, Auxerre, 59 : 

33-266, pis. i-n. 
Phillips, J. 1829. Illustrations of the geology of Yorkshire, xvi + 192 pp., 10 + 14 pis. 

York. 
Piette, E. 1864-91. Gasteropodes. PaUontologie francaise, terrain jurassique, Paris, 3. 

535 PP-. 92 pis. 
Pulfrey, W. 1963. Kenya. Lexique strat. internal., Paris, 4, 8a. 134 pp. 
Pusch, G. G. 1836-37. Polens Paldontologie. 218 pp., 16 pis. Stuttgart. 
Quennell, A. M., Aitken, W. G. ( & McKinlay, A. C. M. 1957. Tanganyika. Lexique 

strat. internat., Paris, 4, 8c. 171 pp. 
Quennell, A. M., McKinlay, A. C. M., & Aitken, W. G. 1956. Summary of the geology of 

Tanganyika. Part 1 : Introduction and stratigraphy. Mem. geol. Surv. Tanganyika, 

Dar es Salaam, 1. 264 pp., 1 map. 
Quenstedt, F. A. 1843. Das Flozgebirge Wiirtembergs. iv + 558 pp. Tubingen. 

1851-52. Handbuch der Petrefaktenkunde. 792 pp., 62 pis. Tubingen. 

-1856-58. Der Jura. 842 pp., 100 pis. Tubingen. 

1881-84. Gasteropoden. Petrefactenkunde Deutschlands, Leipzig, 7. 867 pp., atlas, 

pis. 185-218. 
Radovanovic, S. 1900. Uber die unterliassische Fauna von Vrska Cuka in Ostserbien. 

Ann. giol. Pen. balkan., Beograd, 5, 2 : 60-70, pi. 1. 
Reck, H. 1921. Ueber eine neue Faunula im Juragebiet der deutsch-ostafrikanischen 

Mittellandbahn. Zbl. Min. Geol. Paldont., Stuttgart, 1921 : 431-436. 
Richardson, G. F. 1843. Geology for beginners. 2nd ed. xx + 616 pp. London. 
Richardson, L. & Tutcher, J. W. 1916. On Pteromya crowcombeia Moore and some species 

of Pleuromya and Volsella from the Rhaetic and Lower Lias. Proc. Yorks. geol. Soc, 

York, 19 : 51-58, pis. 8, 9. 
Roeder, H. A. 1882. Beitrag zur Kenntniss des Terrain a Chailles und seiner Zweischaler in 

der Umgegend von Pfirt im Ober-Elsass. no pp., 4 pis. Strassburg. 
Roemer, F. A. 1835-39. Die Versteinerungen des norddeutschen Oolithen-Gebirges. 218 -f 

60 pp., 20 pis. Hannover. 
Rollier, L. 1911-18. Fossiles nouveaux ou peu connus des terrains secondaires (Meso- 

zoiques) du Jura et des contrees environnantes. Abh. schweiz. paldont. Ges., Genf, 37—44. 

696 + 101 pp., 49 pis. 
Saggerson, E. P. & Miller, J. M. 1957. Geology of the Takabba-Wergudud area, Mandera 

District. Rep. geol. Surv. Kenya, 40. 42 pp., 2 maps. 
Salter, J. W. 1865. Jurassic Gasteropoda and Bivalves. In Strachey, R., Palaeontology 

of Niti in the Northern Himalaya : 89-101, pis. 21-23. Calcutta. 
Schafle, L. 1929. Uber Lias- und Doggeraustern. Geol. paldont. Abh., Jena, 17, 2 : 1-88, 

pis. 1-6. 
Schlippe, A. O. 1888. Die Fauna des Bathonien im oberrheinischen Tieflande. Abh. geol. 

Specialk. Els.-Loth., Strassburg, 4, 4 : 1-267, pl s - I_ 8. 
Schlosser, M. 1881. Die Fauna des Kelheimer Diceras-Kalkes. Erste Abtheilung. 

Vertebrata, Crustacea, Cephalopoda und Gastropoda. Palaeontographica, Stuttgart, 

28 : 41-109, pis. 8-13. 
Schlottheim, E. F. von. 1813. Beitrage zur Naturgeschichte der Versteinerungen in 

geognostischer Hinsicht. Taschenb. Min., Frankfurt-am-Main, 7 : 3-134, pis. 1-4. 
Schmidtill, E. 1926. Zur Stratigraphie und Faunenkunde des Doggersandsteins im nord- 

lichen Frankenjura. Palaeontographica, Stuttgart, 68 : 1-109, pis. 1-6. 



FROM TANGANYIKA AND KENYA 207 

Sharpe, D. 1850. Remarks on the genus Nerinaea, with an account of the species found in 

Portugal. Quart. J. geol. Soc. Lond., 6 : 101-115, pis. 12, 13. 
Smith, W. 1817. Stratigraphical system of organized fossils. 113 pp., table. London. 
Sokolov, D. N. 1912. Types and paratypes of C. F. Rouillier and G. A. Trautschold in 

Fahrenkohl's collection from Galieva. Trav. Mus. giol. Pierre le Gr., St. Petersb., 6 : 

97-119, pis. 2, 3. 
Sowerby, J. i8i2o-22a. The Mineral Conchology of Great Britain. London. (1,1812-15; 

2, 1815-18 ; 3, 1818-21 ; 4 (to pi. 377), 1821-22). For continuation, see Sowerby, J. 

de C., i822a-i846a. 
18206-226. The genera of Recent and fossil shells, for the use of students in conchology and 

geology. Parts 1-8. London. (Continued, parts 9-22, by Sowerby, G. B., not cited in 

this bibliography.) 
Sowerby, J. de C. i822a-^6a. The Mineral Conchology of Great Britain. London. (4, 

pi. 378 onwards, 1822-23 ; 5, 1823-35 '< 7, 1840-46.) For earlier part of work, see 

Sowerby, J. 
18406. Description of fossils from the upper Secondary formation of Cutch collected by 

C. W. Grant. Trans, geol. Soc. Lond. (2) 5 : explan. pis. 21-23. 
1 840c. Descriptions of fossils procured by Capt. Smee and Col. Pottinger in Cutch and 

the desert to the north-east of Cutch. Trans, geol. Soc. Lond. (2) 5 : explan. pi. 61. 
Staesche, K. 1926. Die Pectiniden des schwabischen Jura. Geol. paldont. Abh., Jena 

(N.F.) 15 : 1-136, pis. 1-6. 
Stefanini, G. 1932. Avanzi di Molluschi della " Serie di Lugh " in Somalia. Palaeontogr. 

ital., Siena, 32 : 25-27. 
1939. Molluschi del Giuralias della Somalia. Gasteropodi e Lamellibranchi. Palaeontogr. 

ital., Siena, 32, Suppl. 4 : 103-270, pis. 13-27. 
Stoll, E. 1934. Die Brachiopoden und Mollusken der pommerschen Doggergeschiebe. Abh. 

geol. palaeont. Inst. Greifswald, 13 : 1-62, pis. 1-3. 
Strand, E. 1928. Miscellanea nomenclatorica zoologica et palaeontologica. I— II, Arch. 

Naturgesch., Berlin, 92, A, 8 : 30-75. 
Stremoouchow, D. 1896. Note sur la Posidonomya Buchi, Roemer, des schistes de Bala- 
clava en Crimee. Bull. Soc. Nat. Moscou (n.s.) 9 : 391-395, pi. 10. 
Struckmann, C. 1878. Der obere Jura der Umgegend von Hannover, viii + 169 pp., 8 pis. 

Hannover. 
Stuhlmann, F. 1891. Beobachtungen iiber Geologie und Flora auf der Route Bagamoyo- 

Tabora. Mitt, dtsch. Schutzgeb., Berlin, 4 : 48-58. 

1894a. Forschungsreisen in Usaramo. Mitt, dtsch. Schutzgeb., Berlin, 7 : 225-232. 

18946. Berichte iiber eine Reise im Hinterlande von Bagamoyo, in Ukami and Uluguru. 

Mitt, dtsch. Schutzgeb., Berlin, 7 : 282-291. 
Tate, R. 1870. On the palaeontology of the junction beds of the Lower and Middle Lias 

in Gloucestershire. Quart. J. geol. Soc. Lond., 26 : 394-408, pi. 26. 
1876. Class Lamellibranchiata. In Tate, R. & Blake, G. F., The Yorkshire Lias : 

357-412, pis. 11-14. London. 
Terquem, O. 1855. Paleontologie del'etage inferieur de la formation liasique de la province 

de Luxembourg, Grand-Duche (Hollande) et de Hettange, du departement de la Moselle. 

Me"m. Soc. giol. Fr., Paris (2) 5 : 219-343, pis. 12-26. 
Terquem, O. & Jourdy, E. 1869. Monographie de l'etage bathonien dans le departement de 

la Moselle. Mdm. Soc. geol. Fr., Paris (2) 9 : 1-175, pis. 1-14. 
Thevenin, A. igo6a-2^a. Types du Prodrome de paleontologie stratigraphique universelle 

de d'Orbigny, 1. Ann. Paldont., Paris, 1-12. 189 pp., pis. 1-36. 
19086. Paleontologie de Madagascar. V- Fossiles liasiques. Ann. Paldont., Paris, 

3 : 105-143, pis. 8-12. 
Thompson, A. O. & Dodson, R. G. 1958. Geology of the Derkali-Melka Murri area. Rep. 

geol. Surv. Kenya, Nairobi, 43. 35 pp., 4 maps. 



208 JURASSIC BIVALVIA AND GASTROPODA 

Thompson, A. O. & Dodson, R. G. i960. Geology of the Bur Mayo-Tarbaj area. Rep. 

geol. Surv. Kenya, Nairobi, 47. 49 pp., 3 maps. 
Thomson, J. 1879. Notes on the geology of Usambara. Geogr. J., London (n.s.) 1 : 558-564. 

1881. To the Central African lakes and back. 2 vols. London. 

Thurmann, J. 1833. Essai sur les soulevements jurassiques du Porrentruy. M6m. Soc. 

Hist. nat. Strasbourg, 1, 2, 2 : 1-85, pis. 1-5. 
Thurmann, J. & Etallon, A. 1861-64. Lethea Bruntrutana, ou Etudes paleontologiques 

et stratigraphiques sur le Jura bernois et en particulier les environs de Porrentruy. N. 

Denkschr. schweiz. naturf. Ges., Zurich, 18-20. 500 pp., 62 + 3 pis. 
Tornquist, A. 1893. Fragmente einer Oxfordfauna von Mtaru in Deutsch-Ostafrika, nach 

dem von Dr. Stuhlmann gesammelten Material. Jb. hamburg. wiss. Anst., 10 : 265-288, 

pis. 1-3. 
Trautschold, H. i860. Recherches geologiques aux environs de Moscou. Couche jurassique 

de Galiowa. Bull. Soc. Nat. Moscou, 33, 2 : 338-361, pis. 6-8. 
Van de Poel, L. 1955. Structure du test et classification des nucules. Bull. Inst. Sci. nat. 

Belg., Bruxelles, 31, 3 : 1-11. 
Venzo, S. 1942a. Trigonia (Laevitrigonia) Stefaninii n. sp. del Batoniano dell'Oltregiuba. 

Atti Soc. ital. Sci. nat., Milano, 81 : 210-229, pis- 3. 4- 

19426. Diagnosi di forme nuove. Riv. ital. Paleont., Milano, 48, 3 : 27-29. 

1943- Sul Batoniano a Trigonia dell'Oltre-Giuba settentrionale e del Borana sud-orientale. 

Boll. Soc. geol. ital., Roma, 62 : 27-31. 

1944a. Diagnosi di forme nuove. Riv. ital. Paleont., Milano, 50, 1 : 11-14. 

— 19446. Diagnosi di forme nuove. Riv. ital. Paleont., Milano, 50, 3 : 21-23. 

1944c. Diagnosi di forme nuove. Riv. ital. Paleont., Milano, 50, 4 : 21-22. 

— 1945. Diagnosi di forme nuove. Riv. ital. Paleont., Milano, 51, 1 : 15-20. 

- 1949. II Batoniano a Trigonia dell 'Oltregiuba settentrionale e del Borana sud-orientale 

(Africa orientale). Palaeontogr. ital., Pisa, 45 : 111-177, pis. 14-16. 
Yokes, H. E. 1946. Contributions to the paleontology of the Lebanon Mountains, Republic 

of Lebanon. Part 3. The pelecypod fauna of the " Olive Locality " (Aptian) at Abeih. 

Bull. Amer. Mus. nat. Hist., N.Y., 87 : 139-215, pis. 1-10. 
Voltz, P. L. 1835. (M. Voltz expose ensuite les caracteres des Nerinees et en decrit douze 

especes nouvelles.) L'Institut, Paris, 3 : 425-426. 
Waagen, W. 1867. Uber die Zone des Ammonites Sowerbyi. Geogn .-palaont . Beitr., 

Miinchen (edit. Benecke, E. W.), 1 : 509-667, pis. 24-34. 
Weir, J. 1929. Jurassic fossils from Jubaland, East Africa, collected by V. G. Glenday, and 

the Jurassic geology of Somaliland. Monogr. Geol. Dept. Hunterian Mus. Glasgow Univ., 

3 : 1-63, pis. 1-5. 

1930. Mesozoic Brachiopoda and Mollusca from Mombasa. Monogr. Geol. Dept. 

Hunterian Mus. Glasgow Univ., 4 : 75-102, pis. 9-1 1. 

1938. The Jurassic faunas of Kenya with descriptions of some Brachiopoda and Mollusca. 

Monogr. Geol. Dept. Hunterian Mus. Glasgow Univ., 5 : 17-60, pis. 1-4. 

Wenz, W. 1938-44. Gastropoda. Allgemeiner Teil und Prosobranchia. Handbuch der 

Paldozoologie (edit. Schindewolf, O. H.), 6. xii + 1639 pp. Berlin. 
Wetzel, W. 191 i. Faunistische und stratigraphische Untersuchung der Parkinsonien- 

schichten des Teutoburger Waldes bei Bielefeld. Palaeontogr aphica, Stuttgart, 58 : 

139-277, pis. 11-20. 
Whidborne, G. F. 1883. Notes on some fossils, chiefly Mollusca, from the Inferior Oolite. 

Quart. J . geol. Soc. Lond., 39 : 487-540, pis. 15-19. 
Williams, L. A. J. 1962. Geology of the Hadu-Fundi Isa area, north of Malindi. Rep. 

geol. Surv. Kenya, Nairobi, 52. 62 pp., 2 maps. 
Woods, H. 1899-1913. A monograph of the Cretaceous Lamellibranchia of England. 

1 (1899-1903, xliii + 232 pp., 42 pis.) ; 2 (1904-13, vi + 473 pp., 62 pis.). Palaeontogr. 

Soc. [Monogr.'], London. 



FROM TANGANYIKA AND KENYA 209 

Young, G. & Bird, J. 1822. A geological survey of the Yorkshire coast. 235 pp., 17 pis. 

Whitby. 

1828. A geological survey of the Yorkshire coast. 2nd ed. 366 pp., 17 pis. Whitby. 

Zieten, C. H. von. 1830-33. Die V ersteinerungen Wilrttembergs. 102 pp., 72 pis. Stuttgart. 
Zittel, K. A. 1870. Die Fauna der aeltern Cephalopoden fuehrenden Tithonbildungen. 

Palaeontographica, Stuttgart, Suppl. 2 : 1-192, atlas, pis. 1-15. 



-2IO 



INDEX TO SYSTEMATIC DESCRIPTIONS 
New taxonomic names are printed in bold type. 



Acesta, 62 

acmon (aff.), Ataphrus, 143 

Acteonina, 173 

aequalis, Mactvomya, 97 

aequilatera, Rollieria, 29 

africana, Exelissa, 157 

africana, Protocardia, 101 

africana, Trochopsidea, 143 

africanum, Eotrapezium ?, 112 

Africoconulus, 141 

Africomiodon, 117 

aitkeni, Astarte, 87 

aitkeni, Bathrotomaria, 138 

aitkeni, Pseudomelania (Oonia), 151 

A key a, 174 

albus (aff.), Eopecten, 54 

alimena, Liostrea (Catinula) , 72 

ambongoensis, Weyla, 59 

Ampullospira, 164 

anatinus, Modiolus, 37 

Anisocardia, no 

Apolinter, 33 

Arcomytilus, 41 

arkelli, Anisocardia, no 

asaharbitensis, Corbula, 124 

asaharbitensis, Palaeoneilo, 25 

aspasia, Pseudomelania, 147 

asper, Brachidontes {Arcomytilus), 41 

Astarte, 82, (sp.) 85 

Ataphrus, 143 

aubryi, Eopecten, 52 

auritus, Camptonectes, 54 

aviculoides, Gervillella, 44 

ayersi, Anisocardia, in 

ayersi, Astarte, 86 

ayersi, Cuspidaria, 136 

badiensis, Chlamys (Spondylopecten ?), 58 

Bahevellia, 42 

bannesiana, Protocardia (Tendagurium) , 105 

baroni, Eomiodon, 114 

basochiana, Ceratomyopsis, 106 

Bathrotomaria, 138 

bellozanensis, Nuculoma (Palaeonucula) , 25 

besairiei, Ampullospira, 164 

besairiei, Protocardia, 102 

biiniensis, Lima (Plagio stoma) , 59 

bipartitus , Modiolus, 37 

bipi, Protocardia, 103 

Bositra, 50 



Bourguelia, 152 
Brachidontes, 41 
brevicostata (cf.), Trigonia, 76 
briconense, Entolium, 51 
buchii, Bositra, 50 
buchii, Pinna, 45 
bussagensis, Cryptaulax, 160 

calceiformis, Pleuromya, 132 

camelorum, Nuculana (Praesaccella), 2.i 

Camptonectes, 54 

Catinula, 72 

Ceratomya, 132 

Ceratomyopsis, 106 

Chartronella, 145 

Chlamys, 55 

Chrysostoma, 142 

cingulatum, Entolium, 52 

Cirrus, 146 

c/io, Pseudonerinea, 172 

Coelastarte, 93 

Coeloslylina, 152 

concentrica, Ceratomya, 132 

conica, Pseudomelania {Oonia), 150 

consobrina, Protocardia, 103 

constantini, Pinna, 46 

Corbula, 120 

corneolum, Entolium, 51 

Cossmannea, 169 

costata, Lopha, 66 

costata, Trigonia, 74 

Cryptaulax, 160 

Ctenostreon, 66 

Cucullaea, 34 

curta, Opisthotrigonia, 81 

curvivarians, Chlamys, 55 

Cuspidaria, 136 

cutleri, Eomiodon {Africomiodon), 117 

cutleri, Lima {Acesta), 63 

cutleri, Lucina, 96 

cutleri, Nerinella, 170 

Dacryomya, 26 
dainellii, Trigonia, 77 
dejanira, Ampullospira, 165 
depressa, Trochalia, 172 
despecta, Lucina, 95 
didimtuensis, Anisocardia, no 
didimtuensis, Astarte, 84 
didimtuensis, Corbula, 120 



INDEX 



didimtuensis, Discohelix, 137 
didimtuensis, Gevvillella, 43 
didimtuensis, Pleuromya, 131 
dietrichi, Coelastarte, 93 
dietrichi, Mytilus {Falcimytilus), 40 
dietrichi, Pseudomelania (Oonia), 150 
dietrichi, Trigonia (Indotrigonia), 79 
Dietrichiella, 141 
dilata, Osteomya, 129 
dinosaurianum, Eomiodon, 116 
Discohelix, 137 
dodsoni, Exelissa, 158 
dodsoni, Nuciilana (Dacryomya), 27 
dubiensis, Liostrea, 71 
duplicata, Pseudolimea, 64 
dusseensis, Pietteia, 162 
dusseensis, Pseudomelania, 148 
dwanikana, Laevitrigonia, 80 

eamesi, Corbula, 123 
eamesi, Mactromya, 96 
echinata, Meleagrinella, 48 
Eligmus, 47 
elongata, Trigonia, 76 
Entolium, 51 
Eomiodon, 114 
Eonavicula (spp. A, B), 35 
Eopecten, 52 
Eotrapezium, 112 
episcopalis, Astarte, 88 
eruca, Lopha, 69 
excentrica, Ceralomya, 135 
Exelissa, 157 
Exogyra, 73 

Falcimytilus, 39 

Fimbria (spp. A, B, C), 98-100 

Frenguelliella, 78 

gea (aff.), Neritoma (Neridomus) , 144 

Gervillella, 43 

Gervillia, 45 

gigas (aff.), Purpuroidea, 155 

Globularia, 166 

gmuelleri, Stegoconcha, 47 

Goniomya, 129 

Grammatodon, 30 

gregarea, Lopha, 68 

Gryphaea, 73 

Hamusina, 146 
Harpagodes, 162 
hemicardia, Pkoladomya, 127 



hemisphaerica, Globularia, 166 

hennigi, Cossmannea, 169 

hennigi, Globularia, 167 

hennigi, Gryphaea, 73 

hennigi, Lopha, 71 

Hippopodium, 82 

hobleyi, Astarte (Leckhamptonia) , 92 

Homomya, 127 

hortulana, Homomya, 128 

huralensis, Astarte, 89 

imbricatus , Modiolus, 36 

Indogrammatodon, 31 

Indotrigonia, 78 

inequicostata, Chlamys (Radulopecten) , 57 

inequivalvis, Oxytoma, 47 

Inoperna, 38 

inornata, Homomya, 127 

intricata (cf.), Lopha, 69 

iraonensis, Bakevellia, 42 

irritans, Grammatodon {Indogrammatodon) , 32 

janenschi, Seebachia, 94 
jouberti, Quenstedtia, 120 
jumaraensis (cf.), Lima (Plagiostoma), 61 
jurensis, Mytilus (Falcimytilus), 40 

kailtaensis, Corbula, 125 
kenti, Astarte, 85 
kenti, Eotrapezium ?, 113 
kenti, Trigonia, 75 
kenyana, Nuculana (Ryderia), 27 
kenyanus, Africoconulus, 142 
kenyanus, Grammatodon, 30 
kidugalloensis, Corbula, 123 
kidugalloensis, Fimbria, 98 
kidugalloensis, Pronoella, 109 
kidugalloensis, Pseudomelania (Oonia), 149 
kidugalloensis, Trigonia, 75 
kindopeensis, Apolinter, 33 
kindopeensis, Imo (Acesta), 62 
kindopeensis, Lopha ?, 70 
kindopeensis, Musculus, 39 
kindopensis, Scurriopsis (Dietrichiella), 141 
kinjeleensis, Anisocardia, 112 
kinjeleensis, Chlamys (Radulopecten ?), 57 
kipandeensis, Cucullaea, 34 
kiwawaensis, Myophorella, 80 

Laevitrigonia, 80 

laitmairensis, Brachidontes (Ar corny tilus), 41 

Leckhamptonia, 92 

/ews, Thracia, 135 



IXDEX 



Lima, 59 
Limatula, 65 

Liostrea, 71 

/i rata (cf.), Lucina, 95 

lirata, Pholadomya, 126 

Lissochilus, 145 

liter ata, Goniomya, 129 

Lithophaga, 36 

lonjiense, Paracevithium, 159 

lonjiensis, Astarte, 90 

lonjiensis, Pseudorhytidopilus, 139 

Lop ha, 66 

Lucina, (sp.), 94 

lurida, Astarte, 82 

Mactromya, 96 
madridi, Sphaeriola, 101 
mandawaense, Procerithium (Rhabdo- 

colpus), 156 
mandawaensis, Astarte, 90 
mandawaensis, Coelostylina, 153 
mandawaensis, Corbnla, 121 
mandawaensis, Nerinella, 171 
mandawaensis, Pietteia, 161 
mandawaensis, Pseudolimea, 64 
mandawaensis, Zygopleura, 154 
manderaensis, Myopholas, 130 
manderaensis, Tancredia, 119 
matapwaensis, Chlamys, 56 
matapwaensis, Grammatodon (Indo- 

grammalodon) , 32 
mazerasensis, Cirrus, 146 
Meleagrinella, 48 
migeodi, Limatula, 65 
migeodi, Trigonia, 77 
minima, Anisocardia, 112 
mitis, Pinna, 46 
mitoleensis, Astarte, 92 
mitoleensis, Chartronella, 145 
mitoleensis, Nummocalcar, 138 
Modiolus, 36 
moorei, Limatula, 65 
muddoensis, Lima {Plagio stoma) , 60 
muelleri, Astarte, 87 
muelleri, Nerinella, 169 
Musculus, 39 
Myopholas, 130 
Myophorella, 79 
Mytilus, 39 

namgaruensis, Eomiodon, 116 
nana, Exogyra, 73 
Neridomus, 144 



Nerinella, 169 
Neritoma, 144 
Nuculana, 26 
Nuculoma, 25 
Nummocalcar, 138 

oceani (aff.), Harpagodes, 162 

olimvallata, Lopha, 68 

Oonia, 149 

opalini (aff.), Promathildia, 168 

Opisthotrigonia, 81 

orientalis, Gervillella, 43 

Osteomya, 129 

ovalis, Pholadomya, 126 

Oxytoma, 47 

Palaeoneilo, 25 

Palaeonucula, 25 

Paracerithium, 159 

Parallelodon, 29 

perplicatus, Modiolus (Inoperna), 39 

phasianelloides, Globularia, 166 

Pholadomya, 125 

Pictavia, 167 

Pietteia, 160 

pindiroensis, Astarte, 86 

pindiroensis, Corbula, 122 

pindiroensis, Parallelodon, 29 

pindiroensis, Pronoella, 108 

Pinna, 45 

pittieri, Ceratomya, 133 

Plagiostoma, 59 

Pleuromya, 131 

polymorpha, Liostrea, 72 

Praeconia, 94 

Praesaccella, 28 

proboscideum, Ctenostreon, 66 

Procerithium, 156 

Promathildia, 168 

Pronoella, 108 

propebanneiana, Protocardia (Tendagurium) , 

106 
protei, Pholadomya, 126 
Protocardia, 10 1 
Pseudolimea, 64 
Pseudomelania, 147 
Pseudonerinea, 172 
Pseudorhytidopilus , 139 
Pteria, 42 

pulfreyi, Astarte, 83 
Purpuroidea, 155 
putealis, Pronoella, 109 












INDEX 



213 



quadrata, Mactromya, 97 
quennelli, Ampullospira, 165 
quennelli, Fimbria, 99 
quennelli, Myophorella, 79 
quenstedti, Hippopodium, 82 
Quenstedtia, 119 

radiata, Meleagrinella, 48 
Radulopecten, 57 
rahmuensis, Homomya, 128 
rahmuensis, Lima (Plagiostoma), 61 
rahmuensis, Protocardia, 104 
recki, Astarte, 91 
reticulata, Pholadomya, 125 
Rhabdocolpus , 156 
Rhabdoconcha, 151 
rhomboidalis , Praeconia, 94 
rollandi, Eligmus, 47 
Rollieria, 29 
Rutitrigonia, 81 
Ryderia, 27 

saemanni, Bourguetia, 152 

saggersoni, Gervillia, 45 

saggersoni, Quenstedtia, 119 

schardti (cf.), Lima {Plagiostoma) , 60 

schencki, Protocardia, 104 

Scurriopsis, 141 

Seebachia, 94 

siliqua, Gervillella, 44 

smeei, Trigonia (Indotrigonia), 78 

solitaria, Lopha, 69 

somaliensis, Bositra, 50 

sowerbianus , Modiolus (Inoperna) , 38 

sowerbyana, Astarte, 88 

Sphaera, 100 

Sphaeriola, 101 

Spondylopecten , 58 

staffi, Chrysostoma, 142 

stefaninii, Rutitrigonia, 81 

Stegoconcha, 47 

stockleyi, Coelostylina, 152 

stockleyi, Grammatodon (Indogrammatodon), 

stockleyi, Pietteia, 160 
stremmei, Lissochilus, 145 
Striactaeonina, 173 
striata, Cer atomy op sis, 107 
subcorrugata, Sphaera, 100 
sublaevigatus, Grammatodon, 30 



sublaeviuscula, Lima (Plagiostoma), 62 
subminima, Astarte, 84 
suboblonga, Lithophaga, 36 
subobovata, Astarte, 91 
subtextoria, Cklamys, 55 
suprajurensis, Protocardia, 105 
supraliasica, Acteonina (Striactaeonina), 

173 
supraliasica, Purpuroidea, 155 
Symmetrocapulus (sp.), 140 

Tancredia (spp. A, B), 118 
tanganyicensis, Akera, 174 
tanganyicensis, Cer atomy a, 132 
tanganyicensis, Corbula, 122 
tanganyicensis, Eomiodon, 115 
tanganyicensis, Pictavia, 167 
tanganyicensis, Pteria, 42 
tealei, Trigonia (Frenguelliella) , 78 
Tendagurium, 105 
thirriae, Harpagodes, 163 
thompsoni, Eotrapezium ?, 113 
thompsoni, Hamusina, 146 
thompsoni, Nuculana (Dacryomya), 26 
Thracia, 135 
thurmanni, Eopecten, 53 
tifoensis, Lopha, 70 
tifoensis, Mytilus (Falcimytilus) , 39 
trapezicostata, Goniomya, 129 
Trigonia, 74 
Trochalia, 172 
Trochopsidea, 143 

uniformis, Pleuromya, 131 
unilateralis, Astarte, 87 

viceliacensis, Thracia, 135 

virgatus, Grammatodon (Indogrammatodon), 

3i 

virgulinus, Modiolus, 38 
vittata, Pseudomelania, 148 

weissermeli, Astarte, 92 
Weyla, 59 

wilderriensis, Cerafowzya, 134 
wilderriensis, Pseudomelania (Rhabdo- 
concha), 151 
wimmisensis, Ceratomya, 133 

Zygopleura, 154 




PLATE i 

Fig. i. Palaeoneilo asaharbitensis sp. nov. Bathonian [? or Callovian], Asaharbito 
Beds, i mile N. of Asaharbito, N.E. Kenya. Holotype, L. 83864, x 1 . . p. 25 

Figs. ia, b, c. Nuculana (Dacryomya) dodsoni sp. nov. Bathonian-Callovian, Bur Mayo 
Limestones. Hagardulun, 25 miles N.E. of Tarbaj, N.E. Kenya, a, type series 
(L.98274) on bedding plane, x 1 ; b, small group of paratypes, x 2 ; c, holotype, 
L. 98280, x 2 . . . . . . . . . . . . . P- 27 

Figs. 3a, b. Nuculoma (Palaeonucula) bellozanensis (de Loriol). Upper Kimmeridgian, 
Dakacha Limestones. 2 miles S. of Melka Dakacha, N.E. Kenya. Holotype, L.92293 : 
a, x 1 ; b, x 2-5 . . . . . . . . . . . . P- 25 

Figs. 4a, b, c. Nuculana (Dacryomya) thompsoni sp. nov. Upper Lias, Toarcian. 
Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35000 : a, x 1 ; b, 
c, x 2-25 . . . . . . . . . . . . . p. 26 

Figs. 5a, b, c. Rollieria aequilatera (Koch & Dunker). Upper Lias, Toarcian. Didimtu 
hill, 2 miles S. of Bur Mayo, N.E. Kenya. LL.35005 : a, x 1 ; b, c, x 3 . p. 29 

Figs. 6a, b, c. Nuculana (Ryderia) kenyana sp. nov. Upper Lias, Toarcian. Didimtu 
hill, 2 miles S. of Bur Mayo, N.E. Kenya. Holotype, L. 35001 : a, x 1 ; b, c, x 2, 
posterior end of shell restored .......... p. 27 

Figs, ya, b. Parallelodon pindiroensis sp. nov. Bajocian (?), Pindiro Shales. Lihima- 
liao creek, Mandawa area, Tanganyika. Holotype, LL. 35086, x 1 . . . p. 29 

Figs. 8a, b. Same species, horizon and locality. Paratype, LL. 35087, x 1 . p. 29 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE i 




PLATE 2 

Figs. \a, b, c. Grammatodon kenyanus sp. nov. Upper Lias, Toarcian. Didimtu hill, 
2 miles S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35006 : a, x 1 ; b, c, x 2 . p. 30 

Figs. 2a, b. Same species, horizon and locality. Paratype, LL. 35007 ; a, X 1 ; 
b, x 2 . . . . . . . . . . . . p. 30 

Fig. 3. Grammatodon (Indogrammatodon) irritans (Hennig). Upper Kimmeridgian, 
" Trigonia smeei " Bed. 4th Kipande flag, W. of Tendaguru hill, Tanganyika. L.52698, 
XI p. 32 

Fig. 4. Grammatodon {Indogrammatodon) virgatus (J. de C. Sowerby). Callovian ? 
Lonji creek, W. of Mandawa, Tanganyika. Right valve, LL. 35089, x 1 . . . p. 31 

Fig. 5. Same species, horizon and locality. Left valve, LL. 35090, x 1 . . p. 31 

Figs. 6a, b. Grammatodon {Indogrammatodon) matapwaensis sp. nov. Upper Kim- 
meridgian, N. of Matapwa, Pindiro area, Tanganyika. Holotype, LL.35091 : a, x 1 ; 
b, x 3 p. 32 

Fig. 7. Grammatodon sublaevigatus (Zieten). Bathonian [? or Callovian], Asaharbito 
Beds. 1 mile N. of Asaharbito, N.E. Kenya. L.83683, x 1 . . . . p. 30 

Figs. 8a, b. Eonavicula sp. " A ". Callovian [?-Lower Oxfordian], Muddo Erri 
Limestones. Muddo Erri, 12 miles W. of Rahmu, N.E. Kenya. L. 92046, x 1 . P- 35 

Fig. 9. Grammatodon (Indogrammatodon) stockleyi Cox. Upper Oxfordian, Seir 
Limestones. Wilderri hill, 11 miles S.S.W. of Rahmu, N.E. Kenya. L. 92249, x 1 p. 31 

Figs. 10a, b. Nuculana (Praesaccella) camelorum sp. nov. Toarcian or Bajocian, top 
of Didimtu Beds. Camel track about 5 miles S. of Singu, N.E. Kenya, a, type series 
(L.98280) on bedding plane, x 1 ; holotype (bottom right-hand corner) and group of 
paratypes, x 2 . . . . . . . . . . . p. 28 



Bull. B.M. (N.H.) Geol. Suppt. i 




PLATE 3 



Figs, la, b. Cucullaea kipandeensis sp. nov. Upper Kimmeridgian, Nerinella Bed. 
Kipande path, W. of Tendaguru, Tanganyika. Holotype, L. 53146, x 1 . . p 

Fig. 2. Eonavicula sp. " B ". Upper Kimmeridgian, Nerinella Bed. Kindope, N.N.W. 
of Tendaguru, Tanganyika. LL.11517, x 1 . . . . . . . p 

Figs, 3a, b. Apolinter kindopeensis sp. nov. Upper Kimmeridgian, Nerinella Bed. 
Kindope, N.N.W. of Tendaguru, Tanganyika. Holotype, L. 56243 : a, x 1 ; b, x 2 p 

Figs. 4a, b. Same species, horizon and locality. Paratype, L. 56244 : a, x 1 ; 
b, x 2 . . . . . . . . . . . . • P 

Fig. 5. Modiolus imbricatus (J. Sowerby). Oxfordian, Golberobe Beds. Tifo, 14 miles 
N. of Wergudud, N.E. Kenya. L.93579, x 1 . . . . . . p 

Fig. 6. Same species. Bajocian (?), Pindiro Shales. Lihimaliao creek, Mandawa area, 
Tanganyika. LL. 35196, XI. . . . . . . . . • P 

Fig. 7. Modiolus anatinus (Smith). Bajocian, Station Beds. Kidugallo Station, 
Central Railway, Tanganyika. LL. 11554, x 1 . . . . . . . p 

Fig. 8. Modiolus virgulinus (Thurmann & Etallon). Upper Kimmeridgian, Dakacha 
Limestones. 3 miles N.E. of Melka Dakacha, N.E. Kenya. L.92181, x 1 . . p 

Fig. 9. Modiolus bipartitus (J. Sowerby). Upper Kimmeridgian, " Trigonia smeei " 
Bed. Tingutitinguti creek, Tendaguru, Tanganyika. L.52087, x 1 . . p 

Fig. 10. Modiolus {Inoperna) sowerbianus (d'Orbigny). Upper Lias, Toarcian. 
Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya. LL. 35010, x 1 . . . p 

Fig. 11. Same species, horizon and locality. LL.35011, x 1 . . . p 

Fig. 12. Mytilus {Falcimytilus) tifoensis sp. nov. Oxfordian, Golberobe Beds. Ogar 

p 

P 
Tenda- 

P 

Trigonia 

P 
P 



Wein hills, 17 miles N.W. of Wergudud, N.E. Kenya. Holotype, L. 93615, x 1 
Fig. 13. Same species, horizon and locality. Paratype, L. 9361 7, x 1 
Fig. 14. Modiolus {Inoperna) perplicatus (Etallon). Upper Kimmeridgian. 

guru, Tanganyika. L.52153, x 1 . 

Fig. 15. Mytilus {Falcimytilus) dietrichi sp. nov. Upper Kimmeridgian, " 

smeei " Bed. Tendaguru, Tanganyika. Holotype, L.52187, x 1 . 

Fig. 16. Same species, horizon and locality. Paratype, L. 52188, x 1 



34 

35 

33 

33 

36 

36 

37 

38 

37 

38 
38 

39 
39 

39 

40 
40 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 3 




PLATE 4 

Figs. la, b. Musculus kindopeensis sp. nov. Upper Kimmeridgian, Nerinella Bed. 
Kindope, N.N. W. of Tendaguru, Tanganyika. Holotype, LL.11331 : a, x 1 ; b, x 3 p. 39 

Figs. ia, b. Brachidontes [Arcomytilus) asper (J. Sowerby). Callovian [?-Lower 
Oxfordian], Muddo Erri Limestones. Kulong, 2 miles S.W. of Muddo Erri, N.E. Kenya. 
L.92067 : a, x 1 ; b, x 2 . . . . . . . . . . p. 41 

Fig. 3. Brachidontes [Arcomytilus) laitmairensis (de Loriol). Upper Kimmeridgian. 
N. of Matapwa, Pindiro area, Tanganyika. LL. 35094, X 1-5 . . . . p. 41 

Fig. 4. Pteria tanganyicensis sp. nov. Upper Oxfordian. Usigiwa river, 6 miles 
W. S.W. of Kiwangwa, Bagamoyo hinterland, Tanganyika. Holotype, LL. 16793, x 1 p. 42 

Figs. 5a, b. Gervillella didimtuensis sp. nov. Upper Lias, Toarcian. Didimtu hill, 
2 miles S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35012 : a, exterior ; b, interior, 
showing hinge-teeth, both x 1 . . . . . . . . . . p. 43 

Fig. 6. Same species, horizon and locality. Paratype, LL.35013 : interior, showing 
hinge-teeth, x 1 . . . . . . . . . . . . p. 43 

Figs, ja, b. Gervillella orientalis (Douville). Bajocian (?), Pndiro Shales. Near site 
of Mandawa well no. 1, Tanganyika. LL.35197, x 1 . . . . . . P- 43 

Fig. 8. Same species, horizon and locality. LL. 35198, x 1 . . . . P- 43 

Fig. 9. Pinna buchii Koch & Dunker. Bajocian (?), Pindiro Shales. Near site of 
Mandawa well no. i, Tanganyika. LL. 35095, x 1 . . . . . . p. 45 

Fig. 10. Gervillella siliqua (Eudes-Deslongchamps). Oxfordian, Golberobe Beds. 
Tifo, 14 miles N. of Wergudud, N.E. Kenya. L. 92032, x 1 . . . . p. 44 

Fig. 11. Gervillia saggersoni sp. nov. Oxfordian, Golberobe Beds. Korkai Hara- 
massa, 19 miles E. of Takabba, N.E. Kenya. Holotype, L. 93622, x 1 . . . P- 45 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 4 




PLATE 5 

Figs. la, b. Meleagrinella radiata (Trautschold). Upper Kimmeridgian, " Trigonia 
smeei " Bed. Tapaira trail, S. of Tendaguru, Tanganyika. Right valve, L. 52166 : 
a, x 1 ; b, x 2 . . . . . . . . . . . p. 48 

Figs. ia, b. Same species and horizon. Tingutitinguti creek, Tendaguru, Tanganyika. 
Left valve, L. 52090 : a, X 1 ', b, X 2 . . . . . . . . p. 48 

Figs. 3a, b. Same species. Oxfordian, Golberobe Beds. Korkai Hammassa, 19 
miles E. of Takabba, N.E. Kenya. Left valve, L.93649 : a, X 1 ; b, X 2 . . p. 48 

Figs. 4a, b. Same species. Upper Kimmeridgian, " Trigonia smeei " Bed. Road to 
Kindope, N. of Tendaguru, Tanganyika. Left valve, L. 51 136 : a, x 1 ; b, x 2 . p. 48 

Fig. 5. Eligmiis rollandi Douville. Callovian [?-Lower Oxfordian], Muddo Erri 
Limestones. 6 miles W. of Rahmu, N.E. Kenya. L. 92 104, x 1 . . . . P- 47 

Fig. 6. Same species and horizon. 14 miles W.S.W. of Rahmu, N.E. Kenya. 
L.83893, xi p. 47 

Fig. 7. Oxytoma inequivalvis (J. Sowerby). Callovian. Chinamba, f mile S. of 
Amboni quarries, Tanga, Tanganyika. Left valve, LL.35166, x 1 . . . P- 47 

Fig. 8. Stegoconcha gmnelleri (Krenkel). Upper Kimmeridgian, Nerinella Bed. N. of 
Kipande north flag, Tendaguru, Tanganyika. L. 51 168, x 1 . . . . p. 47 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 5 




PLATE 6 

Fig. i. Bositra buchii (Roemer). Lower Bajocian (Aalenian). Borehole at Lugoba, 
Tanganyika, L.82585, x 2 . . . . . . . . . . p. 50 

Fig. 2. Bositra somaliensis (Cox). Upper Kimmeridgian, Nerinella Bed. Kindope, 
N.N.W. of Tendaguru, Tanganyika. L. 51207, x 1 . . . . . p. 50 

Fig. 3. Eopecten aubryi (Douville). Callovian. Manyuli stream, just W. of Nautope, 
Tanganyika. Right valve, L. 93550, x 1 . . . . . . . . p. 52 

Fig. 4. Same species. Upper Oxfordian. Mandawa-Lonji creek traverse, Tanganyika. 
Left valve, LL.35199, x 1 . . . . . . . . . . p. 52 

Fig. 5. Entolium cingulatum (Goldfuss). Upper Jurassic. 5 miles N.E. of Tengeni, 
N.E. Tanganyika. LL. 35202, x 1 . . . . . . . . . p. 52 

Fig. 6. Entolium briconense (Cossmann). Callovian. 2^ miles N. of Msaka road 
junction, Bagamoyo district, Tanganyika. LL. 35168, X 3 . . . . . p. 51 

Fig. 7. Eopecten aff. albns (Quenstedt). Upper Oxfordian, Seir Limestones. Wilderri 
hill, 11 miles S.S.W. of Rahmu, N.E. Kenya. Left valve, L. 92247, x 1 . . . p- 54 

Fig. 8. Eopecten thurmanni (Brauns). Upper Oxfordian, Seir Limestones. 7 miles 
N.N.E. of Raiya hills. N.E. Kenya. Left valve, L. 83900, x 1 . . . P- 53 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 6 



2 








4s. J$ 



PLATE 7 

Figs, la, b. Clilamys matapwaensis sp. nov. Upper Kimmeridgian. Just N. of 
Matapwa, Pindiro area, Tanganyika. Holotype, LL. 35096 : a, x 1 ; b, x 3 . p. 56 

Figs. 2a, b. Same species, horizon and locality. Paratype, LL. 35097 : a, x 1 ; 
b, x 2 . . . . . . . . . . . . . . p. 56 

Fig. 3. Chlamys (Spondylopecten ?) badiensis Cox. Probably Callovian, Namakambe 
stream, Mandawa-Mahokondo anticline, Tanganyika. L. 93552, x 1 . . . p. 58 

Fig. 4. Same species. Callovian. \ mile N.W. of bridge over Mkulumuzi river, 
2 miles W. of Tanga, Tanganyika. LL. 35099, x 1 . . . . . p. 58 

Fig. 5. Chlamys (Radulopecten) inaequicostata (Young and Bird). Upper Oxfordian, 
Seir Limestones. Dusse, 1^ miles S.E. of Rahmu, N.E. Kenya. L. 92228, x 1 . P- 57 

Figs. 6a, b. Chlamys {Radulopecten ?) kinjeleensis sp. nov. Upper Kimmeridgian. 
Mpilepile stream bed, near Mitole, northern Mandawa area, Tanganyika. Paratype, 
LL.35098 : a, x 1 ; b, x 3 p. 57 

Figs, ja, b. Same species. Upper Kimmeridgian, Nerinella Bed. N. of Kinjele, N.W. 
of Tendaguru, Tanganyika. Holotype, L. 51955 : a, x 1 ; b, x 3 . . . P- 57 

Fig. 8. Chlamys subtextoria (Miinster). Callovian. S. of Tarawanda, 11 miles S.E. of 
Lugoba, Tanganyika. L.54116, x 1 . . . . . . . . p. 55 

Figs, ga, b, c. Weyla ambongoensis (Thevenin). Upper Lias, Toarcian. Didimtu hill, 
2 miles S. of Bur Mayo, N.E. Kenya. LL.35017 : a, left valve, X 1 ; b, right valve, 
x 1 ; c, ornament of ribs of right valve, X 3 . . . . . . . p. 59 

Figs. 10a, b. Lima (Plagiostoma) rahmuensis sp. nov. Oxfordian, Rahmu Shales. 
z\ miles S.W. of Rahmu, N.E. Kenya. Holotype, L. 83892 : a, x 1 ; b, ornament, x 
25 . . . . . . . . . . . . p. 61 



Bull. B.M. (N.H.) Geol. Suppt i. 



PLATE 7 




PLATE 8 

Fig. i. Lima (Plagiostoma) biiniensis sp. nov. Bathonian, Murri Limestones. 2 miles 
W. of Melka Biini, N.E. Kenya. Holotype, L. 92174, x 1 . . . . . p- 59 

Fig. 2. Lima (Plagiostoma) muddoensis sp. nov. Callovian [?-Lower Oxfordian], 
Muddo Erri Limestones. Muddo Erri, 12 miles W. of Rahmu, N.E. Kenya. Holotype, 
L.92065, xi. . . . . . . . . . . . . p. 60 

Fig. 3. Pseudolimea mandawaensis sp. nov. Upper Oxfordian. Lihimaliao creek, 
Mandawa area, Tanganyika. Holotype, LL.35100, x 1 . . . . . p. 64 

Figs. 4a, b. Limatula migeodi sp. nov. Upper Kimmeridgian, Nerinella Bed. Kindope, 
N.N.W. of Tendaguru, Tanganyika. Holotype, LL.11514 : a, x 1 ; b, x 3 . p. 65 

Fig. 5. Lima (Plagiostoma) sublaeviuscula Krumbeck. Upper Kimmeridgian, Dakacha 
Limestones. 5 miles S. of Galgali Gambo, N.E. Kenya. L. 83906, x 1 . . p. 62 

Fig. 6. Same species, horizon and locality. L. 83905, x 1 . . . . p. 62 

Figs. qa t b. Limatula moorei sp. nov. Upper Oxfordian. Usigiwa river, 6 miles 
W.S.W. of Kiwanga, Tanganyika. Holotype, LL. 16799 : a, x 1 ; b, x 3 . p. 65 

Figs. 8a, b. Pseudolimea duplicata (J. de C. Sowerby). Upper Kimmeridgian, 
Nerinella Bed. Kindope, N.N.W. of Tendaguru, Tanganyika. LL.11323 : a, X 1 ; 
b, X 3 p. 64 

Fig. 9. Lima (Acesta) cutleri sp. nov. Upper Kimmeridgian, " Trigonia smeei " Bed. 
Tingutitinguti creek, Tendaguru, Tanganyika. Holotype, L. 52033, x 1 . . p. 63 

Fig. 10. Lima (Acesta) kindopeensis sp. nov. Upper Kimmeridgian, Nerinella Bed. 
Kindope, N.N.W. of Tendaguru, Tanganyika. Holotype, L. 56240, x 1 . . p. 62 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 8 




PLATE 9 

Figs. la, b, c. Lopha costata (J. de C. Sowerby). Upper Lias, Toarcian. Didimtu hill, 
2 miles S. of Bur Mayo, N.E. Kenya. LL. 35025 : a, left valve ; b, ventral view ; 
c, right valve, all x 1 . . . . . . . . . . p. 66 

Figs. 2a, b. Lopha olimvallata nom. nov. Upper Lias, Toarcian. Didimtu hill, 

2 miles S. of Bur Mayo, N.E. Kenya. LL. 35026 : a, interior of left valve ; b, posterior 
side of left valve, attached to sheet of fibrous calcite, both x 1 . . . p. 68 

Fig. 3. Liostrea polymorpha (Miinster). Upper Oxfordian. Lihimaliao creek, 
Mandawa area, Tanganyika. Left valve, LL. 35102, x 1 . . . . p. 72 

Fig. 4. Lopha solitaria (J. de C. Sowerby). Upper Oxfordian, Seir Limestones. Dusse, 
i£ miles S.E. of Rahmu, N.E. Kenya. LL. 92224, x 1 . . . . . p. 69 

Fig. 5. Lopha gregarea (J. Sowerby). Upper Kimmeridgian, Dakacha Limestones. 

3 miles N.E. of Melka Dakacha, N.E. Kenya. L.92179, x 1 . . . p. 68 
Figs. 6a, b. Liostrea (Catinula) alimena (d'Orbigny). Callovian [?-Lower Oxfordian], 

Muddo Erri Limestones. 10 miles W. of Rahmu, N.E. Kenya. L. 92137 : a, left valve ; 
b, posterior view, both x 1 . . . . . . . . . . p. 72 

Figs, ja, b. Liostrea polymorpha (Miinster). Upper Oxfordian. Lihimaliao creek, 
Mandawa area, Tanganyika. LL.35103 : a, left valve, with second specimen broadly 
attached to it : b, right valve, both x 1 . . . . . . . . p. 72 

Figs. 8a, b. Lopha cf. intricata (Contejean). Oxfordian, Rahmu Shales. b\ miles 
S.S.W. of Rahmu, N.E. Kenya. L. 83899 : a, large attachment area of left valve ; b, right 
valve, both x 1 . . . . . . . . . . . . p. 69 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 9 




PLATE 10 

Fig. i. Lopha? tifoensis sp. nov. Oxfordian, Golberobe Beds. Tifo, 14 miles N. of 
Wergudud, N.E. Kenya. Paratype, L.93561, x 1 . . . . . . p. 70 

Fig. 2. Same species, horizon and locality. Paratype, L.93580, x 1 . . p. 70 

Fig. 3. Lopha? kindopeensis sp. nov. Upper Kimmeridgian, Nerinella Bed. Kindope, 
N.N.W. of Tendaguru, Tanganyika. Holotype, L. 54855, interior of right valve, x 1 p. 70 

Figs. 4a, b. Same species, horizon and locality. Paratype, L. 54858, ventral part of 
left valve : a, exterior ; b, interior, both x 1 . . . . . . . p. 70 

Fig. 5. Same species, horizon and locality. Paratype, L. 54856, interior of right valve, 
XI . . . . . . . . . . . . . . p. 70 

Fig. 6. Lopha tifoensis sp. nov. Oxfordian, Golberobe Beds. Tifo, 14 miles N. of 
Wergudud, N.E. Kenya. Holotype, L. 93574, x 1 . . . . . . p. 70 

Fig. 7. Same species, horizon and locality. Paratype, L. 93563, x 1 . . . p. 70 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 10 




PLATE ii 

Figs. la, b. Gryphaea hennigi Dietrich. Upper Oxfordian. Hill opposite Kingura 
village, N. of Wami river, Bagamoyo hinterland, Tanganyika. LL. 16848, x 1 . P- 73 

Figs. 2a, fe. Trigonia costa ta Parkinson. Bajocian. Magole, 5 miles N.W. of Kidugallo, 
Tanganyika. LL. 35104 : a, x 1 ; b, x 2 . . . . . . . P- 74 

Figs. 3a, b, c. Trigonia kidugalloensis sp. nov. Bajocian. \\ miles N.N.W. of 
Kidugallo, Tanganyika. Holotype, LL. 35105 : a, b, side and dorsal views, x 1 ; 
c, side view, x 2 . . . . . . . . . . . p. 75 

Figs. 4a, b, c. Trigonia kenti sp. nov. Bajocian. 6 miles N.W. of Kidugallo, Tangan- 
yika. Holotype, LL.35107 : a, b, side and dorsal views, X 1 ; c, side view, x 2 . P- 75 

Fig. 5. Exogyra nana (J. Sowerby). Oxfordian, Rahmu Shales. i\ miles S.W. of 
Rahmu, N.E. Kenya. L. 83889, x 1 . . . . . . . . . p. 73 

Figs. 6a, b. Same species, horizon and locality. L. 83891, x 1 . . . P- 73 

Fig. 7. Trigonia cf. brevicostata Kitchin. Bathonian [? or Callovian], Asaharbito 
Beds. 1 mile N. of Asaharbito, N.E. Kenya. LL.11380, x 1 . . . . p. 76 

Fig. 8. Trigonia elongata J. de C. Sowerby. Callovian ? i£ miles W. of Mandawa, 
Tanganyika. LL. 35109, x 1 . . . . . . . . . p. 76 

Fig. 9. Trigonia dainellii Venzo. Uppermost Jurassic or basal Cretaceous, Danissa 
Beds. W. slope of hill £ mile E. of Hafura, N.E. Kenya. L. 92270, x 1 . . . P- 77 

Fig. 10. Trigonia (Frenguelliella) tealei Cox. Callovian. S. of Tarawanda, 11 miles 
S.E. of Lugoba, Tanganyika. Holotype, L. 541 13, x 1 . . . . . p. 78 

Figs. 11a, b. Trigonia migeodi sp. nov. Upper Kimmeridgian, Nerinella Bed. 1 mile 
N.W. of Tendaguru, Tanganyika. Holotype, L. 51 193 : a, x 1 ; b, x 2-4 . . p. 77 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE ii 




PLATE 12 

Figs, la, b. Myophorella quennelli sp. nov. Kimmeridgian. W. of Mabokweni, 4 
miles N.W. of Tanga, Tanganyika. Holotype, LL.11809 : a, x 1 ; b, x 2 . p. 79 

Figs. 2a, 6. Myophorella kiwawaensis sp. nov. Upper Kimmeridgian. Kiwavva stream, 
2400 yards S.E. of Mitekera survey beacon, northern Mandawa area, Tanganyika. 
Holotype, LL.35110 : a, x 1 ; b, x 3 . . . . . . . p. 80 

Figs. 3a, b. Rutitrigonia stefaninii (Venzo). Upper Kimmeridgian, Dakacha Lime- 
stones. 3 miles N.E. of Melka Dakacha, N.E. Kenya. L. 92180 : a, x 1 ; b, x 2 p. 81 

Fig. 4. Opisthotrigonia curta (Aitken). Upper Kimmeridgian. Mpilepile stream, 
800 yards N.E. of Mitole road junction, northern Mandawa area, Tanganyika. LL.35112, 
Xi p. 81 

Fig. 5. Laevitrigonia dwanikana sp. nov. Upper Kimmeridgian, " Trigonia smeei " 
Bed. Dwanika river, N.E. of Tendaguru, Tanganyika. Holotype, L. 52692, x 1 . p. 80 

Figs. 6a, b. Astavte kenti sp. nov. Bajocian (?), Pindiro Shales. Near site of Mandawa 
well no. 1, Tanganyika. Holotype, LL.35113 : a, x 1 ; b, x 2 

Figs, ja, b. Same species, horizon and locality. Paratype, LL.35114 : a, x 

b, X 2 

Fig. 8. Astarte lurida J. Sowerby. Upper Lias, Toarcian. Didimtu hill, 2 miles S. 

Bur Mayo, N.E. Kenya. LL. 35044, x 1 . 

Figs, ga, b, c. Astarte aitkeni sp. nov. Callovian. Nchia stream, 2 miles W.N.W. 
Mandawa, Tanganyika. Holotype, LL. 35189 : a, left valve, x 1 ; b, left valve, x 

c, dorsal view, x 2 . 
Figs. 10a, b, c. Astarte didimtuensis sp. nov. Upper Lias, Toarcian. Didimtu hill, 

2 miles S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35032 : a, left valve, x 1 ; b, left 
valve, x 2 ; c, dorsal view, x 2 . . . . . . . . . p. 84 

Figs. 11a, b, c. Same species, horizon and locality. Paratype, LL. 35033 : a, right 
valve, X 1 ; b, right valve, x 2 ; c, dorsal view, x 2 . . . . . p. 84 

Figs. 12a, b. Astarte pulfreyi sp. nov. Upper Lias, Toarcian. Didimtu hill, 2 miles 
S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35027 : a, right valve ; b, dorsal view, both 
Xi p. 83 

Fig. 13. Same species, horizon and locality. Paratype, LL. 35028, x 1 . . p. 83 

Figs. 14a, b. Astarte subminima sp. nov. Upper Lias, Toarcian. Didimtu hill, 2 miles 
S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35042 : a, x 1 ; b, x 3 . . . p. 84 

Figs. 15a, b. Astarte sp. Upper Lias, Toarcian. Didimtu hill, 2 miles S. of Bur Mayo, 
N.E. Kenya. LL. 35043 : a, x 1 ; b, x 3 . . . . . . . p. 85 



p- 


85 


1 ; 




P- 


85 


of 




P- 


82 


of 




2 ; 




P 


87 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 12 




PLATE 13 

Fig. 1. Astarte mitoleensis sp. nov. Upper Kimmeridgian. Mpilepile stream, near 
Mitole, northern Mandawa area, Tanganyika. Holotype, LL. 35123, x 1 . . p. 92 

Fig. 2. Astarte weissermeli Dietrich. Upper Kimmeridgian, " Trigonia smeei " Bed. 
Nitongola creek, Tendaguru, Tanganyika. L. 52120, x 1 . . . . . p. 92 

Fig. 3. Same species. Upper Kimmeridgian. Mpilepile stream, near Mitole, northern 
Mandawa area, Tanganyika. LL. 35204, x 1 . . . . . . p. 92 

Figs. 4a, b. Astarte pindiroensis sp. nov. Bajocian (?), Pindiro Shales. 1 mile S.E. 
of Nkomore, Mandawa-Mahokondo area, Tanganyika. Holotype, LL. 35206 : a, x 1 ; 
b, X 4 . . . . . . . . . . . . p. 86 

Figs. 5a, b. Same species, horizon and locality. Paratype, LL. 35207 : a, x 1 ; 
b, x 4 . . . . . . . . . . . . p. 86 

Figs. 6a, b. Astarte sowerbyana Holdhaus. Upper Oxfordian. Lihimaliao creek, 
Mandawa area, Tanganyika. LL.35120 : a, left valve ; b, dorsal view, both x 1 . p. 88 

Figs, ja, b. Astarte ayersi sp. nov. Bathonian [? or Callovian], Asaharbito Beds. 
1 mile N. of Asaharbito, N.E. Kenya. Holotype, L.83876 : a, x 1 ; b, x 2 . p. 86 

Fig. 8. Astarte episcopalis de Loriol. Upper Oxfordian. Usigiwa river, 6 miles 
W.S.W. of Kiwangwa, Tanganyika. LL. 16839, x 1 . . . . . p. 88 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 13 










PLATE 14 

Fig. 1. A starte lonjiensis sp. nov. Upper Kimmeridgian. Lonji creek, W. of Mandawa, 
Tanganyika. Holotype, LL. 35122, x 1 . . . . . . . . p. 90 

Fig. 2. Astarte unilateralis J. de C. Sowerby. Callovian ? Lonji creek, VV. of Mandawa, 
Tanganyika. LL.35118, x 1 . . . . . . . . . . p. 87 

Fig. 3. Same species, horizon and locality. LL.35119, x 1 . . . . p. 87 

Fig. 4. Astarte recki Dietrich. Upper Kimmeridgian, Nerinella Bed. Beyond N.W. 
flag, 1 mile N.W. of Tendaguru, Tanganyika. L.51186, x 1 . . . . . p. 91 

Fig. 5. Same species, horizon and locality. L. 51 188, x 1 . . . . p. 91 

Figs. 6a, b. Astarte mandawaensis sp. nov. Upper Kimmeridgian. Lonji creek, W. 
of Mandawa, Tanganyika. Holotype, LL.35121 : a, exterior ; b, hinge-teeth (left 
valve), both x 1 . . . . . . . . . . . . p. 90 



Bull. B.M. (N.H.) Geol Suppt. i 



PLATE 14 




PLATE 15 

Fig. 1. Astarte huralensis Stefanini. Upper Oxfordian, Seir Limestones. Dusse, i\ 
miles S.E. of Rahmu, N.E. Kenya. L. 92236, group of specimens, x 1 . . . p. 89 

Figs. 2a, b. Astarte (Leckhamptonia) hobleyi sp. nov. Upper Lias, Toarcian. 
Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya. Holotype, LL.35045 : a, X 1 ; 
b, x i-6 P- 92 

Figs. 3a, b. Lucina cutleri sp. nov. Upper Kimmeridgian, " Trigonia smeei " Bed. 
Lilomba creek, Tendaguru, Tanganyika. Holotype, L.52141 : a, x 1 ; b, x 2 . p. 96 

Fig. 4. Astarte subobovata Dietrich. Upper Kimmeridgian, " Trigonia smeei " Bed. 
Maimbwi river, S.E. of Tendaguru, Tanganyika. L. 52683, x 1 . . . p. 91 

Figs. 5a, b. Lucina sp. Upper Lias, Toarcian. Didimtu hill, 2 miles S. of Bur Mayo, 
N.E. Kenya. LL. 35047 : a, side view ; b, dorsal view, both x 1 . . . P- 94 

Fig. 6. Fimbria sp. " A ". Callovian, Rukesa Shales. 13 miles W. of Rahmu, N.E. 
Kenya. L. 92134, x 1 . . . . . . . . . . . p. 98 

Fig. 7. Mactromya aequalis Agassiz. Callovian [?-Lower Oxfordian]. Kulong, 
2 miles S. of Muddo Erri, N.E. Kenya. L. 92072, x 1 . . . . . p. 97 

Figs. 8a, b, c. Mactromya eamesi sp. nov. Bajocian (?), Pindiro Shales. Near side of 
Mandawa well no. 1, Tanganyika. Holotype, LL. 35127 : a, left valve, X 1 ; b, left 
valve, x 2 ; c, dorsal view, x 1 . . . . . . . . . p. 96 

Fig. 9. Lucina despecta Phillips. Bajocian. ij miles E. of Kidugallo Station, 
Tanganyika. L. 54090, x 1-5 . . . . . . . . . p. 95 

Fig. 10. Fimbria sp. " C ". Upper Kimmeridgian. Lonji creek, W. of Mandawa, 
Tanganyika. LL. 35126, x 1 . . . . . . . . . .p. 100 

Figs. 11a, b. Mactromya quadrata (Roemer). Upper Oxfordian, Seir Limestones. 
17 miles S. of Rahmu, N.E. Kenya. L. 92218 : a, left valve (imperfect) ; b, dorsal view, 
both xi ............. p. 97 

Fig. 12. Fimbria sp. " B ". Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 
Muddo Erri, N.E. Kenya. L.92048, x 1 . . . . . . . p. 99 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 15 




,• 


Wv>m 


Wi 


tf> . 


1 






a 


'iM 








' "« * . 



PLATE 16 

Figs. la, b. Fimbria kidugalloensis sp. nov. Bajocian. i\ miles E. of Kidugallo 
Station, Tanganyika. Holotype, L. 54 103 : a, x 1 ; b, ornament, x 4-3 . . p. 98 

Figs. ia, b, c. Protocavdia africana sp. nov. Upper Lias, Toarcian. Didimtu hill, 
2 miles. S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35603 : a, left valve, x 1 ; b, left 
valve, x 2 ; c, dorsal view, x 1 . . . . . . . . .p. 101 

Fig. 3. Sphaeriola madridi (d'Archiac). Bathonian [? or Callovian], Asaharbito Beds. 
1 mile N. of Asaharbito, N.E. Kenya. L. 83867, associated left and right valves, x 1 p. 101 

Fig. 4. Same species, horizon and locality. L. 83870, left valve, x 1 . .p. 101 

Fig. 5. Protocardia consobrina (Terquem & Jourdy). Callovian. Changogo-Magindu 
track, 4 miles from Changogo town, Tanganyika. LL. 35132, x 1 . . .p. 103 

Fig. 6. Protocardia (Tendagurhim) propebanneiana (Dietrich). Upper Kimmeridgian, 
" Trigonia smeei " Bed. Tingutitinguti creek, Tendaguru, Tanganyika. L. 52084, x 1 p. 106 

Fig. 7. Fimbria quennelli sp. nov. Upper Oxfordian. Usigiwa river, 6 miles W.S.W. 
of Kiwangwa, Tanganyika. Holotype, LL.16841, x 1 . . . . . p. 99 

Fig. 8. Protocardia besairiei sp. nov. Bajocian (?), Pindiro Shales. Lihimaliao creek, 
Mandawa area, Tanganyika. Holotype, LL. 35128, x 1 . . . . .p. 102 

Figs, ga, b. Same species. Bajocian. Mont Bovy, Maevatanana, N.W. Madagascar. 
Paratype, L. 74976 : a, right valve ; b, dorsal view, both x 1 . . . .p. 102 

Fig. 10. Same species, horizon and locality. Paratype, L. 74977, right valve, x 1 p. 102 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 1 6 




PLATE 17 

Fig. 1. Protocardia bipi sp. nov. Bajocian (?), Pindiro Shales. Lihimaliao creek, 
Mandawa area, Tanganyika. Paratype. LL. 35130, x 1 . . . . p 

Fig. 2. Same species, horizon and locality. Paratype, LL. 35131, X 1 . . p 

Figs. 3a, b. Same species, horizon and locality. Holotype, LL. 35129 : a, left valve ; 
b, dorsal view, both XI. ■ • • • • • • • • .p 

Figs. 4a, b. Protocardia rahmuensis sp. nov. Oxfordian, Rahmu Shales. 5^ miles 
S.W. of Rahmu, N.E. Kenya. Holotype, L. 92257 : a, x 1 ; b, x 2-2 . . . p 

Figs. 5a, b. Protocardia schencki Miiller. Upper Kimmeridgian, " Trigonia smeei " Bed. 
Tingutitinguti creek, Tendaguru, Tanganyika. L.52038 : a, x 1 ; b, X 2 . . p 

Fig. 6. Protocardia suprajurensis (Conte jean). Upper Kimmeridgian. N. of Matapwa, 
Pindiro area, Tanganyika. LL. 35134, x i-i . . . . . . p 

Fig. 7. Ceratomyopsis basochiana (Defrance). Callovian. 2 miles E. of Magindu 
Station, Tanganyika. L. 67164, xi. . . . . . . . .p 

Figs. 8a, b. Same species. Callovian [?-Lower Oxfordian], Muddo Erri Limestones. 
Kulong, 2 miles S.W. of Muddo Erri, N.E. Kenya. L. 92082 : a, left valve ; b, posterior 
end, both xi. . . . . . . . . . . . .p 

Fig. 9. Ceratomyopsis striata (d'Orbigny). Kimmeridgian, Hereri Shales. Hereri 
river crossing, 3 miles S. of Melka Kunha, N.E. Kenya. L. 92191, x 1 . . . p 

Fig. 10. Pronoella putealis sp. nov. Bajocian (?), Pindiro Shales. Lihimaliao creek, 
Mandawa area, Tanganyika. Paratype, LL.35142, x 1-5 . . . . . p 

Fig. 11. Same species, horizon and locality. Holotype, LL.35 141, x 1-5 . . p 

Fig. 12. Pronoella pindiroensis sp. nov. Bajocian (?), Pindiro Shales. Lihimaliao 
creek, Pindiro area, Tanganyika. Paratype, LL. 35159 ; hinge-teeth of right valve, x 1 p 

Fig. 13. Same species and horizon. Near site of Mandawa well no. 1, Tanganyika. 
Paratype, LL.35 138, X 1 . . . . . . . . ■ • • P 

Figs. 14a, b. Same species, horizon and locality. Holotype, LL. 35135 : a, right 
valve ; b, dorsal view, both xi. . . . . . . . .p 

Fig. 15. Same species, horizon and locality. Paratype, LL. 35136, x 1 . . p 

Fig. 16. Same species and horizon. Lihimaliao creek, Pindiro area, Tanganyika. 
Paratype, LL.35 140, Xi ........ ..p 

Figs. 17a, b. Same species and horizon. Near site of Mandawa well no. 1, Tanganyika. 
Paratype, LL. 35137 : a, right valve ; b, dorsal view, both x 1 . . . . p 



103 

103 

103 
104 
104 

105 
106 

106 

107 

109 
109 

108 

108 

108 
108 

108 

108 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 17 




PLATE 18 

Figs, xa, b. Pronoella kidugalloensis sp. now Bajocian. i \ miles N.N.W. of Kidugallo, 
Tanganyika. Holotype, LL. 35143 : a, right valve ; b, dorsal view, both x 1 . p. 109 

Figs, za, b. Eotrapezium? thompsoni sp. nov. Upper Lias, Toarcian. Didimtu hill, 
2 miles S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35061 : a, right valve ; b, dorsal 
view, both x 1 ............ p. 

Fig. 3. Anisocardia kinjeleensis sp. nov. Upper Kimmeridgian. Kinjele, 5 miles W. 
of Mtapaia, Tanganyika. Holotype, L. 51938, x 1 . . . . . .p. 

Fig. 4. Anisocardia didimtuensis sp. nov. Upper Lias, Toarcian. Didimtu hill, 2 miles 
S. of Bur Mayo, N.E. Kenya. Holotype, LL.35056, x 1 . . . . .p. 

Figs. 5a, b. Anisocardia arkelli sp. nov. Upper Lias, Toarcian. Didimtu hill, 2 miles 
S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35051 : a, left valve ; b, dorsal view, both x 1 p. 

Figs. 6a, b. Anisocardia ayersi sp. nov. Upper Lias, Toarcian. Didimtu hill, 2 miles 
S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35057 : a, right side ; b, dorsal view, both 
XI p. 

Figs, ya, b. Eotrapezium? africanum sp. nov. Upper Lias, Toarcian. Didimtu hill, 
2 miles S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35058 : a, right side of internal 
mould ; b, dorsal view, both x 1 . . . . . . . . .p. 

Fig. 8. Anisocardia minima (J. Sowerby). Callovian, Rukesa Shales. 13 miles W. of 
Rahmu, N.E. Kenya. L. 92120, X 1 . . . . . . . . .p. 

Figs, ga, b. Eotrapezium? kenti sp. nov. Bajocian. 5 miles N.W. of Kidugallo, 
Tanganyika. Holotype, a left valve, LL. 35144 : a, exterior ; b, hinge-teeth, both x 1 p. 113 

Figs. 10a, b. Same species, horizon and locality. Paratype, LL. 35145 : a, right 
valve : b, dorsal view, both X 1 . . . . . . . . . p. 113 

Fig. 11. Eomiodon baroni (Newton). Bajocian (?). 1 mile N.N.E. of Ngerengere, 
Tanganyika. LL.7210, x 1 . . . . . . . . . p. 114 

Figs. 12a, b. Eomiodon tanganyicensis sp. nov. Bajocian (?). 1 mile N.N.E. of 
Ngerengere, Tanganyika. Holotype, a right valve, LL.7215 : a, exterior ; b, interior, 
both XI . . . . . . . . . . . . . p. 115 

Fig. 13. Same species, horizon and locality. Paratype, LL.7214, x 1 . . p. 115 

Figs. 14a, b. Eomiodon namgaruensis sp. nov. Jurassic. 1 mile E.S.E. of Uleka, 
Marudyi-Namgaru area, Tanganyika. Holotype, LL.35146 : a, right valve ; b, dorsal 
view, both X 1 . . . . . . . . . . . . p. 116 

Figs. 15a, b. Eomiodon dinosanrianum sp. nov. Upper Kimmeridgian. Tendaguru, 
Tanganyika. Paratype, L. 53323 : a, X I ; b, X 3 . . . • . . p. 116 

Figs. 16a, b. Same species, horizon and locality. Holotype, L. 53322 : a, X 1 ; 
b, X 3 . p. 116 

Fig. 17. Eomiodon (Africomiodon) cutleri sp. nov. Upper Kimmeridgian, " Trigonia 
smeei " Bed. Tingutitinguti creek, Tendaguru, Tanganyika. Paratype, L. 51998, hinge- 
teeth of left valve, X2. . . . . . . . . . P- 117 

Figs. 18a, b. Same species, horizon and locality. Holotype, a right valve, L. 5 1995 : 
a, exterior. X 1 ; b, interior, X2. . . . . . . . . p. 117 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 1 8 




PLATE 19 

Fig. 1. Tancredia manderaensis sp. nov. Uppermost Jurassic, Gudediye Beds. 
Matasafara, 15 miles W. of Mandera, N.E. Kenya. Latex " squeeze " from holotype, 
LL. 35190, xi . . . . . . . . . . . . p. 119 

Fig. 2. Tancredia sp. " A ". Oxfordian, Golberobe Beds. Korkai Hammassa, 19 
miles E. of Takabba, N.E. Kenya. L. 93625, x 1 . . . . . . p. 118 

Fig. 3. Tancredia sp. " B ". Oxfordian, Golberobe Beds. Ogar Wein, 17 miles N.W. 
of Wergudud, N.E. Kenya. L. 93614, x 1 . . . . . . . .p. 118 

Fig. 4. Quenstedtia saggersoni sp. nov. Oxfordian, Golberobe Beds. Ogar Wein, 
17 miles N.W. of Wergudud, N.E. Kenya. Holotype, L. 93600, x 1 . . .p. 119 

Fig. 5. Quenstedtia jouberli sp. nov. Upper Kimmeridgian, Dakacha Limestones. N. 
of Figfirya, northern Raiya hills, N.E. Kenya. Holotype, L. 922 13, x 1 . . . p. 120 

Fig. 6. Quenstedtia saggersoni sp. nov. Oxfordian, Golberobe Beds. Korkai Ham- 
massa, 19 miles E. of Takabba, N.E. Kenya. Paratype, L. 93636, x 1 . . . p. 119 

Figs, ja, b. Corbula mandawaensis sp. nov. Bajocian (?). Depth 48-50 feet, Mandawa 
well no. 6, Tanganyika. Paratype, LL. 35149, a right valve : a, x 1 ; b, x 4 . p. 121 

Figs. 8a, b. Same species. Bajocian (?). Depth 46-48 feet, Mandawa well no. 6, 
Tanganyika. Holotype, LL.35 148, a left valve : a, x 1 ; b, x 4 . . . p. 121 

Figs, ga, b. Corbula tanganyicensis sp. nov. Bajocian (?). Depth 4510-4520 feet, 
Mandawa well no. 7, Tanganyika. Paratype, LL.35151 : a, X I ; b, X 5 . . p. 122 

Fig. 10. Corbula didimtuensis sp. nov. Upper Lias, Toarcian. Didimtu hill, 2 miles 
S. of Bur Mayo, N.E. Kenya. Paratype, LL.35074, x 1 . . . . . p. 120 

Figs. 11a, b, c. Same species, horizon and locality. Holotype, LL. 35073 : a, left 
valve ; b, right valve ; c, dorsal view, all x 1 . . . . . . . p. 120 

Figs. 12a, b, c, d. Corbula tanganyicensis sp. nov. Bajocian (?). Depth 4510-4520 feet, 
Mandawa well no. 7, Tanganyika. Holotype, LL. 35150 : a, x 1 ; b, left valve, x 5 ; 
c, dorsal view, X 5 ; d, right valve, X 5 . . . . . . . . p. 122 

Figs. 13a, b. Corbula kailtaensis sp. nov. Oxfordian, Golberobe Beds. Kailta, 
Golberobe hills, N.E. Kenya. Holotype, L. 92036 : a, x 1 ; b, x 2 . . . p. 125 

Figs. 14a, b, c. Corbula pindiroensis sp. nov. Bajocian (?). Depth 166-170 feet, 
Pindiro well no. 1, Tanganyika. Holotype, LL. 35152 : a, right valve, x 1 ; b, right 
valve, x 2 ; c, left valve, x 2 ......... p. 122 

Figs. 15a, b. Same species. Bajocian (?). Depth 170-174 feet, Pindiro well no. 1, 
Tanganyika. Paratype, LL. 35153 : a, left valve, X 1 ; b, left valve, x 2 . . p. 122 

Fig. 16. Pleuromya didimtuensis sp. nov. Upper Lias, Toarcian. Didimtu hill, 
2 miles S. of Bur Mayo, N.E. Kenya. Holotype, LL. 35079, x 1 . . . . p. 131 

Figs. 17a, b, c. Corbula kidugalloensis sp. nov. Bajocian. 5 miles N.W. of Kidugallo, 
Tanganyika. Holotype, LL. 35154 : a, left valve, X 1 ; b, left valve, x 2 ; c, dorsal 
view, x 2 ............. p. 123 

Figs. 18a, b. Corbula asaharbitensis sp. nov. Bathonian [? or Callovian], Asaharbito 
Beds. 1 mile N. of Asaharbito, N.E. Kenya. Holotype, LL. 13230, a left valve : a, x 1 ; 
b, X 5 p. 124 

Figs. 19a, b, c. Corbula earnest sp. nov. Bajocian. 6 miles N.W. of Kidugallo, 
Tanganyika. Holotype, LL. 35155 : a, left valve, X 1 ; b, left valve, x 2 ; c, dorsal 
view, x 2 ............. p. 123 

Fig. 20. Myopholas manderaensis sp. nov. Uppermost Jurassic, Gudediye Beds. 
Matasafara, 15 miles W. of Mandera, N.E. Kenya. Holotype, L. 92271, x 1 . . p. 130 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 19 





PLATE 20 

Fig. 1. Pholadomya ovalis (J. Sowerby). Callovian [?-Lower Oxfordian], Muddo Erri 
Limestones. Kulong, 2 miles S.W. of Muddo Erri, N.E. Kenya. L. 92075, x 1 . p. 126 

Fig. 2. Pholadomya reticulata Agassiz. Upper Lias, Toarcian. Didimtu hill, 2 miles 
S. of Bur Mayo, N.E. Kenya. LL. 35076, x 2 . . . . . . .p. 125 

Figs. 3a, b. Homomya rakmuensis sp. nov. Oxfordian, Rahmu Shales. Uacha, 6 miles 
S. of Rahmu, N.E. Kenya. Holotype, L. 92260 : a, right valve ; b, dorsal view, both 
xi p. 128 

Fig. 4. Homomya hortulana Agassiz. Upper Kimmeridgian, Nerinella Bed. N. of 
Kipande, Tendaguru, Tanganyika. L. 51 177, x 1 . . . . . .p. 128 

Fig. 5. Pholadomya hemicardia Roemer. Upper Oxfordian. Mandawa-Lonji creek 
traverse, Mandawa area, Tanganyika. LL. 35156, x 1 . . . . .p. 127 

Fig. 6. Pleuromya uniformis (J. Sowerby). Upper Kimmeridgian. Kinjele, 5 miles 
W. of Mtapaia, Tanganyika. L. 51934, x 1 ....... p. 131 

Fig. 7. Ceratomya concentrica (J. de C. Sowerby). Callovian [?-Lower Oxfordian], 
Muddo Erri Limestones. Kulong, 2 miles S.W. of Muddo Erri, N.E. Kenya. L.92084, 
X 1 .............. p. 132 

Fig. 8. Pholadomya livata (J. Sowerby). Callovian. 2 miles E. of Magindu Station, 
Tanganyika. L.54120, x 1 . . . . . . . . . .p. 126 

Fig. 9. Pleuromya calceiformis (Phillips). Upper Oxfordian. Mandawa-Lonji creek 
traverse, Mandawa area, Tanganyika. LL. 35158, x 1 ..... p. 132 

Fig. 10. Ceratomya excentrica (Roemer). Kimmeridgian, Hereri Shales. Hereri river 
crossing 3, miles S. of Melka Kunha, N.E. Kenya : L. 92200, x 1 . . . p. 135 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 20 




PLATE 21 

Figs. la, b, c. Ceratomya tanganyicensis sp. nov. Bajocian (?), Pindiro Shales. 
Lihimaliao creek, Mandawa area, Tanganyika. Holotype, LL.35159 : a, right valve, x 1 
b, dorsal view, X 1 ; c, ornament, x 4 . . . . . . . . p 

Fig. 2. Goniomya trapezicostata (Pusch). Callovian. £ mile N.W. of bridge over 
Mkulumuzi river, 2 miles W. of Tanga, Tanganyika. LL. 35157, x 1 . . . p 

Fig. 3. Same species. Bajocian. i£ miles E. of Kidugallo Station, Tanganyika. 
L. 54080, xi. . . . . . . . . . . . • P 

Fig. 4. Ceratomya pittieri (de Loriol). Callovian. Magindu Station, Tanganyika. 
LL. 35160, xi ............ p 

Fig. 5. Ceratomya wilderriensis sp. nov. Upper Oxfordian, Seir Limestones. Dusse, 
i\ miles S.E. of Rahmu, N.E. Kenya. Holotype, L. 92226, x 1 . . . . p 

Figs. 6a, b. Cuspidaria ayersi sp. nov. Bathonian [? or Callovian], Asaharbito Beds. 
1 mile N. of Asaharbito, N.E. Kenya. Holotype, LL. 13246 : a, x 1 ; b, x 2 . p 

Figs, ya, b. Same species, horizon and locality. Paratype, LL. 13247 : a, x 1 ; 

b, X 3 P 

Fig. 8. Thracia lens (Agassiz). Bajocian (?), Pindiro Shales. Lihimaliao creek, 

Mandawa area, Tanganyika. LL.35161, x 1 . . . . . . . p 

Fig. 9. Thracia viceliacensis (d'Orbigny). Callovian. Lonji creek, Mandawa area, 

Tanganyika. LL. 35162, xi. . . . . . . . . .p 



132 
129 
129 
133 
134 
136 
136 

135 
135 



Bull. B.M. (N.H.) Geol. Suppt i. 



PLATE 21 




PLATE 22 

Figs. la, b, c, d. Discohelix didimtnensis sp. nov. Upper Lias, Toarcian. Didimtu 
hill, 2 miles S. of Bur Mayo, N.E. Kenya. Holotype, GG. 10246 : a, x 1 ; b, upper face, 
x 4 ; c, lower face, X 4 ; d, outer face, x 4 . . . . . . .p. 137 

Figs. 2a, b, c. Numtnocalcar mitoleensis sp. nov. Upper Kimmeridgian. Mpilepile 
stream, E. of Mitole, Tanganyika. Holotype, GG. 10282 : a, upper face ; b, lower face ; 
c, outer face, all x 1 5 . . . . . . . . . . .p. 138 

Figs. 3a, b. Psendorhytidopihis lonjiensis sp. nov. Callovian. Lonji— Runjo stream, 
i£ miles W. of Mandawa, Tanganyika. Holotype, GG.10312 : a, side view ; b, apical 
view, both x 1 ............ p. 139 

Figs. 4a, b. Scurriopsis (Dietrichiella) kindopensis (Dietrich). Upper Kimmeridgian, 
" Trigonia smeei " Bed. Kindope, N.N.W. of Tendaguru, Tanganyika. G. 48913 : 
a, x 1 ; b, x 3 . . . . . . . . . . .p. 141 

Figs. 5a, b. Symmetrocapulus ? sp. Upper Kimmeridgian, " Trigonia smeei " Bed. 
Tingutitinguti creek, Tendaguru, Tanganyika. G. 48031 : a, x 1 ; b, x 3 . . p. 140 

Fig. 6. Bathrotomaria aitkeni sp. nov. Middle-Upper Kimmeridgian. N. Bank of 
Mandawa-Namakongoro stream, about 1 mile W. of Mandawa, Tanganyika. Holotype, 
GG. 10306 : abapertural view, x 1 ........ p. 138 



Bull. B.M. {N.H.) Geol. Suppt. i 



PLATE 22 




PLATE 23 

Figs. 1a, b. Bathrotomaria aitkeni sp. nov. Middle-Upper Kimmeridgian. N. bank 
of Mandawa-Namakongoro stream, about 1 mile W. of Mandawa, Tanganyika. Holotype, 
GG. 10306 : a, apertural view ; b, base, both x 1 . . . . . . p. 138 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 23 



M\ 




PLATE 24 

Figs. 1a, b, c. Chrysostoma staffi Dietrich. Upper Kimmeridgian. Tapaira trail, S. 
of Tendaguru, Tanganyika. G. 48567 : a, x 1 ; b, apertural view, x 2 ; c, abapertural 
view, x 2 ............. p. 142 

Figs, za, b. Ataphrus aff. acmon (d'Orbigny). Bajocian. Kidugallo, Tanganyika. 
G. 26204 : *i X 1 ; 1, X 3 . • • • • • • . . . p. 143 

Figs. $a, b. Chartronella mitoleensis sp. nov. Upper Kimmeridgian. Mpilepile 
stream, about 1 mile N.E. of Mitole, Tanganyika. Holotype, GG.10313 : a, apertural 
view ; b, abapertural view, both x 1 . . . . . . . . p. 145 

Figs. 4a, b. Lissochilus stremmei Dietrich. Upper Kimmeridgian. \\ miles N.W. of 
Mandawa, Tanganyika. GG.10315 : a, apertural view ; b, abapertural view, both x 1 p. 145 

Figs. 5a, b, c, d. Trochopsidea africana sp. nov. Upper Lias, Toarcian. Didimtu hill, 
2 miles S. of Bur Mayo, N.E. Kenya. Holotype, GG. 10258 : a, x 1 ; b, apertural view, 
X 3 ; c, abapertural view, X 3 ; d, base, X 3 . . . . . . .p. 143 

Figs. 6a, b. Pseudomelania (Oonia) dietrichi sp. nov. Upper Kimmeridgian. " Trigonia 
smeei " Bed. Tingutitinguti creek, Tendaguru, Tanganyika. Holotype, G. 48028 : 
a, apertural view ; b, abapertural view, both x 1 . . . . . . p. 150 

Figs, ya, b. Neritoma (Neridomns) aff. gea (d'Orbigny). S. of Tarawanda, 11 miles 
S.E. of Lugoba, Tanganyika. G.61310 : a, x 1 ; b, x 2 . . . . . p. 144 

Figs. 8a, b. Cirrus mazarasensis sp. nov. Bajocian (?), Mazeras Sandstones. Ribe, 
9 miles N.E. of Mazeras, Kenya. Holotype, GG.6524, " squeeze " from natural mould : 
a, x 1 ; b, x 2-5 . . . . . . . . . . . . p. 146 

Figs, ga, b. Hamusina Ihompsoni sp. nov. Upper Lias, Toarcian. Didimtu hill, 
2 miles S. of Bur Mayo, N.E. Kenya. Holotype, GG. 10263 ■ a, x 1 ; b, x 3 . p. 146 

Fig. 10. Pseudomelania aspasia (d'Orbigny). Callovian. Nchia stream, 2 miles 
W. N.W. of Mandawa, Tanganyika. GG.10317, x 1 . . . . .p. 147 

Figs. 11a, b, c. Pseudomelania dusseensis sp. nov. Upper Oxfordian, Seir Limestones. 
Dusse, i£ miles S.E. of Rahmu, N.E. Kenya. Holotype, G. 76399 ; a, x 1 ; b, aper- 
tural view, x 3*7 ; c, abapertural view, x 37 . . . . . .p. 148 

Fig. 12. Pseudomelania vittata (Phillips). Middle-Upper Kimmeridgian. 1 mile 
X. of Manyuli, Tanganyika. GG.10316, X 1 . . . . . . .p. 148 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 24 




PLATE 25 

Figs. la, b, c. Pseudomelania (Oonia) aitkeni sp. nov. Middle-Upper Kimmeridgian. 
Mandawa-Namakongoro stream, 1 mile W. of Mandawa, Tanganyika. Holotype, 
GG.10318 : a, x 1 ; b, apertural view, x 2 ; c, abapertural view, x 2 . . p. 151 

Figs. 2a, b, c. Pseudomelania {Oonia) conica (Morris & Lycett). Bathonian (?). 2 
miles W. of Tengeni, Tanganyika. 00.10463 : a, X 1 ; b, apertural view, x 2 ; 
c, abapertural view, x 2 . . . . . . . . . . .p. 150 

Figs. 3a, b. Zygopleura mandawaensis sp. nov. Bajocian (?). Depth 58-60 feet, 
Mandawa well no. 6, Tanganyika. Paratype, GG. 10287 : «, X 1 ; ft, X 4 . . p. 154 

Figs. 4a, b. Coelostylina mandawaensis sp. nov. Bajocian (?), Pindiro Shales. 
Lihimaliao creek, Mandawa area, Tanganyika. Paratype, GG. 10286, showing aperture : 

a, x 1 ; b, x 3 p. 153 

Figs. 5a, b. Same species and formation. Near site of Mandawa well no. 1, Tanganyika. 

Holotype, GG. 10283 : «, x 1 ; ft, x 3 . . . . . . . . p. 153 

Figs. 6a, b. Same species, formation and locality. Paratype, GG. 10285 : a, x 1 ; 

ft. X 3 p. 153 

Figs, ya, b. Same species, formation and locality. Paratype, GG. 10284 : a, x 1 ; 

b, X 3 p. 153 

Fig. 8. Bourguetia saemanni (Oppel). Upper Oxfordian, Seir Limestones. Dusse, 

1 \ miles S.E. of Rahmu, N.E. Kenya. G.76404, x 1 . . . . . . p. 152 

Fig. 9. Same species. Upper Oxfordian. E. margin of Makoko plain, Bagamoyo 

hinterland, Tanganyika. GG.2182, x 1 . . . . . . .p. 152 

Fig. 10. Pseudomelania (Rhabdoconcha) wilderriensis sp. nov. Upper Oxfordian, Seir 

Limestones. Wilderri hill, 11 miles S.S.W. of Rahmu, N.E. Kenya. Holotype, G. 76414, 

XI p. 151 

Fig. 11. Zygopleura mandawaensis sp. nov. Bajocian (?), Pindiro Shales. Lihimaliao 

creek, Mandawa area, Tanganyika. Holotype, GG. 10465, X 3 . . . .p. 154 



Bull. B.M. (N.H.) Geol. Suppt. i 

A 



PLATE 25 




PLATE 26 

Figs, la, b. Exelissa dodsoni sp. nov. Bathonian-Callovian, Bur Mayo Limestones. 
Hagardulun, 25 miles N.E. of Tarbaj, N.E. Kenya, a, group of specimens, G. 79190, 
showing holotype and numerous paratypes, X 1 ; b, part of same group, with holotype 
near middle of left side of figure, x 4 . . . . . . . . p. 158 

Fig. 2. Purpuroidea aff. gigas (Thurmann & Etallon). Upper Kimmeridgian. £ mile 
N.W. of Mbinga, Tanganyika. GG. 10328, X o-8 ...... p. 155 

Figs. 3a, b, c. Coelostylina stockleyi sp. nov. Bajocian. i\ miles N.N.W. of Kidugallo, 
Tanganyika. Holotype, GG.10281 : a, x 1 ; b, apertural view, x 3 ; c, abapertural 
view, x 3 ............. p. 152 

Figs. 4a, b, c. Pseudomelania (Oonia) kidugalloensis sp. nov. Bajocian. z\ miles N.N.W. 
of Kidugallo, Tanganyika. Holotype, GG. 10280 ; a, x 1 ; b, apertural view, x 3 ; 
c, abapertural view, X 3 . . . . . . . . . . .p. 149 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 26 




PLATE 27 

Figs. la, b. Cryptaulax bussagensis (Cossmann). Bathonian (?). 2 miles W. of 
Tengeni, Tanganyika. GG. 10464 : a, x 1 ; b, x 3 . . . . . . p. 160 

Figs. 2a, b. Exelissa africana sp. nov. Bajocian (?). Depth 58-60 feet, Mandawa well 
no. 6, Tanganyika. Paratype, GG. 10296 : a, x 1 ; b, x 4 . . . . p. 157 

Figs. 3a, b. Same species. Bajocian (?). Depth 52-54 feet, Mandawa well no. 6, 
Tanganyika. Paratype, GG. 10294 '■ a, x 1 ; b, x 4 . . . . . p. 157 

Figs. 4a, b. Same species. Bajocian (?). Depth 58-60 feet, Mandawa well no. 6, 
Tanganyika. Paratype, GG. 10297 '■ a, x 1 ; b, x 4 . . . . . p. 157 

Figs. 5a, b. Same species. Bajocian (?). Depth 58-60 feet, Mandawa well no. 6, 
Tanganyika. Holotype, GG. 10295 '■ a, x 1 ; b, x 4 . . . . . p. 157 

Figs. 6a, b. Paracerithium lonjiense sp. nov. Lower Kimmeridgian. Mandawa-Lonji 
creek traverse, Tanganyika. Paratype, GG. 10299 '■ a, x 1 ; b, x 8 . . . p. 159 

Figs, ja, b. Pietteia stockleyi sp. nov. Bajocian (?). Depth 58-60 feet, Mandawa well 
no. 6, Tanganyika. Paratype, GG. 10300 : a, x 1 ; b, x 4 . . . . p. 160 

Figs. 8a, b. Same species. Bajocian (?). Depth 60-62 feet, Mandawa well no. 6, 
Tanganyika. Paratype, GG.10301 : a, x 1 ; b, x 4 . . . . . p. 160 

Figs, ga, b. Procerithium {Rhabdocolpus) mandawaense sp. nov. Bajocian (?). Depth 
62-64 feet, Mandawa well no. 6, Tanganyika. Paratype, GG.10291 : a, x 1 ; b, x 4 p. 156 

Figs. 10a, b. Same species. Bajocian (?). Depth 46-48 feet, Mandawa well no. 6, 
Tanganyika. Paratype, GG. 10292 : a, x 1 ; b, x 4 . . . . . p. 156 

Figs. 11a, b. Same species. Bajocian (?). Depth 48-50 feet, Mandawa well no. 6, 
Tanganyika. Paratype, GG. 10293 '. a, X 1 ; b, x 4 . . . . . p. 156 

Figs. 12a, b. Same species. Bajocian (?). Depth 46-48 feet, Mandawa well no. 6, 
Tanganyika. Holotype, GG. 10290 : a, x 1 ; b, x 4 . . . . . p. 156 

Figs. 13a, b. Paracerithium lonjiense sp. nov. Lower Kimmeridgian. Mandawa-Lonji 
creek traverse, Tanganyika. Holotype, GG. 10298 : a, x 1 ; b, x 8 . . . p. 159 

Figs. 14a, b, c. Pietteia stockleyi sp. nov. Bajocian (?). Near site of Mandawa well 
no. 1, Tanganyika. Holotype, GG. 10359 : a, x 1 ; b, apertural view, x 4 ; c, abaper- 
tural view, X 4 ............ p. 160 

Fig. 15. Purpuroidea aff. gigas (Thurmann & Etallon). Upper Kimmeridgian. f mile 
N.W. of Mbinga, Tanganyika. GG. 10328, x o-8 ...... p. 155 

Figs. 16a, b, c. Pietteia dusseensis sp. nov. Upper Oxfordian, Seir Limestones. Dusse, 
i£ miles S.E. of Rahmu, N.E. Kenya. Holotype, G. 76405 : a, x 1 ; b, apertural view, 
X 3 ; c, abapertural view, x 3 ......... p. 162 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 27 




PLATE 28 

Fig. 1. Haypagodes thirriae (Contejean). Upper Kimmeridgian, Dakacha Limestones. 
io£ miles S.W. of Raiya hills, N.E. Kenya. Internal mould, G. 70520, x 1 . p. 163 

Fig. 2. Same species, horizon and locality. Internal mould, G. 70519, x 1 . . p. 163 

Fig. 3. Harpagodes aff. oceani (Brongniart) . Callovian. Manyuli stream, just W. of 
Nautope, Tanganyika. GG.10319, x 1 . . . . . . . .p. 162 

Figs. 4a, b. Purpuroidea supraliasica sp. nov. Upper Lias, Toarcian. Didimtu hill, 
2 miles S. of Bur Mayo, N.E. Kenya. Holotype, GG. 10264 : a > apertural view (aperture 
broken) ; b, abapertural view, both x 1 . . . . . . . . p. 155 

Figs. 5a, b, c. Globularia hennigi sp. nov. Upper Kimmeridgian, Dakacha Limestones. 
2 miles S. of Melka Dakacha, N.E. Kenya. Holotype, G. 76391 : a, abapertural view, 
X 1 ; b, abapertural view, x 2 ; c, apertural view, x 1 . . . .p. 167 

Figs. 6a, b, c. Pictavia tanganyicensis sp. nov. Bajocian (?). Near site of Mandawa 
well no. 1, Tanganyika. Holotype, GG. 10302 : a, x 1 ; b, apertural view, x 5 ; 
c, abapertural view, X 5 . . . . . . . . . . .p. 167 

Figs, ja, b. Same species, horizon and locality. Paratype, GG. 10303 : a, x 1 ; 
b, X 5 . . . p. 167 

Fig. 8. Ampullospira dejanira (d'Orbigny). Upper Oxfordian, Seir Limestones. 
Dusse, i\ miles S.E. of Rahmu, N.E. Kenya. G. 76395, x 1 . . . . .p. 165 

Fig. 9. Globularia hemisphaevica (Roemer). Upper Kimmeridgian, Dakacha Lime- 
stones. N. of Figfirya, northern Raiya hills, N.E. Kenya. G. 76384, x 1 . . p. 166 

Fig. 10. Ampullospira besairiei sp. nov. Bajocian. S.W. of geodetic point Antery, 
Maevatanana district, N.W. Madagascar. Paratype, G. 65892, x 1 . . .p. 164 

Figs. 11a, b. Same species. Bajocian (?), Pindiro Shales. Near site of Mandawa well 
no. 1, Tanganyika. Paratype, GG. 10305 : a, apertural view (outer lip broken) ; b, 
abapertural view, both x 1 . . . . . . . . . .p. 164 

Figs. 12a, b. Same species and horizon. Lihimaliao creek, Mandawa area, Tanganyika. 
Holotype, GG. 10304, spire crushed in slightly : a, abapertural view ; b, apertural view, 
both xi ............. p. 164 

Fig. 13. Same species. Bajocian. S.W. of geodetic point Antery, Maevatanana 
district, N.W. Madagascar. Paratype, G.65887, X 1 . . . . . .p. 164 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 28 




PLATE 29 

Figs. la, b. Globularia phasianelloides (d'Orbigny). Upper Oxfordian, Seir Limestones. 
Dusse, i£ miles S.E. of Rahmu, N.E. Kenya. G. 76397 : a, apertural view ; b, abaper- 
tural view, both x 1 ........... p. 166 

Figs. ia, b, c. Ampullospira quennelli sp. nov. Callovian. Nchia stream, 2 miles 
W.N.W. of Mandawa, Tanganyika. Paratype, GG. 10325 : a, apertural view ; b, abaper- 
tural view ; c, apical view, showing sutural channel, all x 1 . . . .p. 165 

Figs. 3a, b, c. Same species. Kimmeridgian. Just W. of Mabokweni, 4 miles N.W. 
of Tanga, Tanganyika. Holotype, G. 91998 : a, apertural view ; b, abapertural view ; 
c, apical view, all x 1 . . . . . . . . . .p. 165 

Figs. \a, b, c. Acteonina (Striactaeonina) supraliasica sp. nov. Upper Lias, Toarcian. 
Didimtu hill, 2 miles S. of Bur Mayo, N.E. Kenya. Holotype, GG.10271 : a, x 1 ; 
b, apertural view, x 2 ; c, abapertural view, x 2 . . . . . . p. 173 

Figs. 5a, b. Akera tanganyicensis sp. nov. Callovian. 1 mile N.W. of Mbinga, 
Tanganyika. Holotype, GG. 10332 : a, apertural view ; b, abapertural view, both x 1 p. 174 

Figs. 6a, b. Promathildia aff. opalini (Quenstedt). Upper Lias, Toarcian. Didimtu 
hill, 2 miles S. of Bur Mayo, N.E. Kenya. GG. 10270 : a, x 1 ; b, x 2 . . p. 168 

Fig. 7. Trochalia depressa (Voltz). Upper Kimmeridgian, Dakacha Limestones. 
Melka Dakacha, N.E. Kenya. G. 76375 : axial section (partly retouched), x 1 . p. 172 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 29 




PLATE 30 

Fig. 1. Nerinella mandawaensis sp. nov. Middle-Upper Kimmeridgian. Mandawa- 
Namakongoro stream, about 1 mile W. of Mandawa, Tanganyika. Paratype, GG. 10334, 
x 11 .............. p 



Figs. 2a, b. Same species, horizon and locality. Holotype, GG. 10333 : a, X 1 ; 
b, x 2 . . . . . . . . . . . . p. 171 

Fig. 3. Same species, horizon and locality. Paratypes, GG. 10335, one seen in axial 
section (partly retouched), x 2 . . . . . . . . . . P- 171 

Figs. 4a, b. Nerinella cutleri sp. nov. Upper Kimmeridgian, Nerinella Bed. Kipande 
path, near Tendaguru, Tanganyika. Holotype, G. 46026 : a, x 1 ; b, x 2 . p. 170 

Fig. 5. Pseudonerinea clio (d'Orbigny). Upper Kimmeridgian. £ mile E. of 
Nangororo, Tanganyika. GG. 10329, x 1 . . . . . . . .p. 172 

Fig. 6. Same species, horizon and locality. GG. 10330, axial section (partly retouched), 
Xi .............. p. 172 

Fig. 7. Cossmannea hennigi (Dietrich). Upper Kimmeridgian, " Trigonia smeei " Bed. 
Tributary of Maimbwi river, near Tendaguru, Tanganyika. G. 48914, x 1 . .p. 169 

Figs. 8a, b. Pieileia mandawaensis sp. nov. Bajocian (?), Pindiro Shales. Near site 
of Mandawa well no. 1, Tanganyika. Holotype, GG. 10382 : a, x 1 ; b, x 4 . p. 161 

Figs, ga, b, c. Africoconulus kenyanus sp. nov. Upper Lias, Toarcian. Didimtu hill, 
2 miles S. of Bur Mayo, N.E. Kenya. Holotype, GG. 10250 : a, apertural view ; b, aba- 
pertural view ; c, base, all x 2 . . . . . . . . .p. 142 



171 



Bull. B.M. (N.H.) Geol. Suppt. i 



PLATE 30 




''' 









Printed in England by Staples Printers Limited at their Kettering, Northants, establishment 






''# 



#> 



STRATIGRAPHY AND PLANKTONIC FORAMINIFElty ^ 
OF THE UPPER CRETACEOUS-LOWER TERTIARY 
SUCCESSION IN THE ESNA-IDFU REGION, 
NILE VALLEY, EGYPT, U.A.R. 



Z. R. EL-NAGGAR 



BULLETIN OF 
THE BRITISH MUSEUM (NATURAL HISTORY) 
GEOLOGY SUPPLEMENT 2 

LONDON : 1966 



( 2 SEI 
STRATIGRAPHY AND PLANKTONIC FORAMINIFERA OF THE-* 

\& 
UPPER CRETACEOUS-LOWER TERTIARY SUCCESSION IN N^jy 

THE ESNA-IDFU REGION, NILE VALLEY, EGYPT, U.A.R. 



BY 



ZAGHLOUL RAGHIB EL-NAGGAR, Ph.D. 

\ /\> 

Dept. of Geology, U.C.W., Aberystwyth, now at University of Riyacjh, 

Saudi Arabia 



23 Plates; 18 Text-figures 



BULLETIN OF 

THE BRITISH MUSEUM (NATURAL HISTORY) 

GEOLOGY SUPPLEMENT 2 

LONDON: 1966 



THE BULLETIN OF THE BRITISH MUSEUM 

(natural history), instituted in 1949, is issued 
in five series corresponding to the Departments of the 
Museum, and an Historical series. 

Parts will appear at irregular intervals as they 
become ready. Volumes will contain about three or 
four hundred pages and will not necessarily be 
completed within one calendar year. 

In 1965 a separate supplementary series of longer 
papers was instituted, numbered serially for each 
Department. 

This paper is Supplement No. 2 of the Geological 
(Palaeontological) series. The abbreviated titles of 
periodicals cited follow those of the World List of 
Scientific Periodicals. 



Trustees of the British Museum (Natural History) 1966 



TRUSTEES OF 
THE BRITISH MUSEUM (NATURAL HISTORY) 

Issued 22nd September, 1966 Price £10 



STRATIGRAPHY AND PLANKTONIC FORAMINIFERA OF THE 

UPPER CRETACEOUS-LOWER TERTIARY SUCCESSION IN 

THE ESNA-IDFU REGION, NILE VALLEY, EGYPT, U.A.R. 

By Z. R. EL-NAGGAR 



CONTENTS 

I. Acknowledgements ....... 

II. Introduction ........ 

III. Stratigraphy ........ 

A. General Discussion ...... 

B. The Upper Cretaceous-Lower Tertiary in Egypt 

C. Summary of the Succession .... 

D. Discussion of the Age ..... 

IV. Palaeontology ........ 

A. The Macrofauna ...... 

B. The Planktonic Foraminifera .... 
V. Systematic Descriptions ...... 

Superfamily GLOBIGERINACEAE Carpenter, Parker & 
Jones ........ 

Family GLOBOTRUNCANIDAE Brotzen 

Genus Abathomphalus Bolli, Loeblich & Tappan 
Abathomphahis intermedia (Bolli) 

mayaroensis (Bolli) . 
Genus Globotvuncana Cushman 

Globotruncana adamsi sp. nov. 

aegyptiaca aegyptiaca Nakkady 
aegyptiaca duwi Nakkady . 
arabica sp. nov. 
area (Cushman) 
bahijae sp. nov. 
conica White 

contusa contusa (Cushman) 
contusa patelliformis Gandolfi 
contusa scutilla Gandolfi 
contusa witwickae subsp. nov. 
cf. convexa Sandidge . 
esnehensis Nakkady & Osman 
fareedi sp. nov. 
fomicata ackermanni Gandolfi 
fornicata cesarensis Gandolfi 
fomicata fornicata Plummer 
fornicata globulocamerata subsp 
nov. .... 

fornicata manaurensis Gandolfi 
fundiconnlosa Subbotina 
gagnebini Tilev 
cf . gagnebini Tilev 



Page 
6 
7 
15 
15 
32 
44 
45 
52 
52 
53 
66 

66 
66 
66 
66 
67 
68 

75 
76 
80 
81 

83 
86 

87 
90 

93 

95 

95 

97 

98 

100 

102 

103 

105 

108 
109 
no 
in 
"3 



UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 



gansseri dicarinata Pessagno 
gansseri gandolfii subsp. nov. 
gansseri gansseri Bolli 
gansseri subgansseri Gandolfi 
havanensis Voorwijk . 
leupoldi Bolli 
lugeoni Tilev 
mariai Gandolfi 
mariei Banner & Blow 
orientalis sp. nov. 
rosetta pettersi Gandolfi 
rosetta rosetta (Carsey) 
sharawnaensis sp. nov. 
stuarti parva Gandolfi 
stuarti stuarti (de Lapparent) 
stuarti stuartiformis Dalbiez 
stuarti subspinosa Pessagno 
subcircumnodifer Gandolfi . 
tricarinata colombiana Gandolfi 
tricarinata tricarinata (Quereau 
ventricosa White 
youssefi sp. nov. 
sp. 
Genus Rugoglobigerina Bronnimann . 

Rugoglobigerina glaessneri Gandolfi 
loetterli (Nauss) 
macrocephala Bronnimann 
pennyi Bronnimann 
pustulata Bronnimann 
rotundata Bronnimann 
rugosa (Plummer) 
Genus Trinitella Bronnimann 

Trinitella scotti Bronnimann . 
Family ROTALIPORIDAE Sigal .... 

Subfamily HEDBERGELLINAE Loeblich & Tappan 
Genus Hedbergella Bronnimann & Brown . 

Hedbergella hessi compressiformis (Pessagno) 
hessi hessi (Pessagno) 
mattsoni (Pessagno) 
monmouthensis (Olsson) 
petaloidea (Gandolfi) 
Family GLOBIGERINIDAE Carpenter, Parker & Jones 
Subfamily GLOBIGERININAE Carpenter, Parker & 
Jones ....... 

Genus Globigerina d'Orbigny .... 

Globigerina alanwoodi sp. nov. 

aquiensis Loeblich & Tappan 

arabica sp. nov. 

bacuana Khalilov 

belli White .... 

chascanona Loeblich & Tappan 
daubjergensis Bronnimann 
haynesi sp. nov. 
inaequispira Subbotina . 
kozlowskii Brotzen & Pozaryska 



114 

115 
117 
119 
120 
121 
122 
123 
124 

125 
127 
128 
130 
131 
133 
136 
139 
140 
141 
142 

143 
144 

H5 
146 
146 
147 
147 
148 
148 
148 
149 
149 
150 
150 
150 
150 
150 
151 
151 
151 
152 
U53 

153 
153 
156 
157 
157 
159 
159 
160 
161 
165 
167 
168 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 



mckannai White . 
nodosa sp. nov. 
soldadoensis Bronnimann 
spiralis Bolli 
stonei Weiss 
triloculinoides Plummer 
triloculinoides parva subsp. nov. 
velascoensis Cushman 
Family GLOBOROTALIIDAE Cushman 
Subfamily GLOBOROTALIINAE Cushman 
Genus Globorotalia Cushman 

Globorotalia acuta Toulmin 

aequa Cushman & Renz 

africana sp. nov. 

angulata abundocamerata Bolli 

angulata angulata (White) 

apanthesma Loeblich & Tappan 

berggreni sp. nov. 

bollii sp. nov. 

compressa (Plummer) 

cf. convexa Subbotina . 

ehrenbergi Bolli 

emilei sp. nov. 

esnaensis (Le Roy) 

faragi sp. nov. 

hispidicidaris Loeblich & Tappan 

imitata Subbotina 

irrorata Loeblich & Tappan . 

kilabiyaensis sp. nov. 

loeblichi sp. nov. . 

nicoli Martin 

occlusa Loeblich & Tappan 

perclara Loeblich & Tappan . 

pseudobulloides (Plummer) 

pseudomenardii Bolli 

pusilla laevigata Bolli 

pusilla meditervanica subsp. nov. 

pusilla pusilla Bolli 

quadrata (White) . 

sibaiyaensis sp. nov. 

tribulosa Loeblich & Tappan . 

trinidadensis Bolli 

troelseni Loeblich & Tappan 

uncinata carinata sub.sp nov. 

uncinata uncinata Bolli 

velascoensis caucasica Glaessner 

velascoensis parva Rey 

velascoensis velascoensis (Cushman) 

whitei Weiss 

wilcoxensis Cushman & Ponton 

woodi sp. nov. 

sp. 



VI. Summary and Conclusions 
VII. References 
VIII. Index .... 



170 
173 
174 

175 
176 
178 
182 
183 
185 
185 

185 
188 
190 

193 
194 
197 
199 
200 
202 
203 
205 
207 
208 
210 
213 
214 

215 
216 
218 
218 
220 
221 
223 
224 
227 
229 
230 
232 
233 
235 
236 
236 
238 
239 
240 
242 

244 
246 
249 
250 
252 
253 
254 
264 
280 



6 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

SYNOPSIS 

The Upper Cretaceous-Lower Tertiary succession of the Esna-Idfu region is examined in 
detail, and the macrofauna as well as the planktonic Foraminifera are used to interpret the 
stratigraphy of the region. A total of 119 species and subspecies of planktonic Foraminifera 
are described, 20 species and 6 subspecies of which are new ; 142 macrofossil species are also 
identified and their ranges given. The succession is divided into distinct litho- and bio-strati- 
graphical units, most of which are new. The position of the Campanian-Maestrichtian boundary 
is suggested, and the Maestrichtian is defined and zoned. It is considered as the uppermost stage 
of the Cretaceous system while the Danian is regarded as the lowermost stage of the Tertiary. 
The Cretaceous-Tertiary boundary is proved to be marked by a distinct break, despite previous 
emphasis on the absolute conformity of the succession. Strata of Danian age, with the typical 
planktonic Foraminifera of the type section have been discovered, and have proved that pre- 
viously recorded Danian strata in Egypt were incorrectly dated. The controversy over Paleocene 
stratigraphy is discussed in detail, and it is recommended that the use of the existing stage names 
(other than Danian) be avoided until their chronological relationships are clarified. A three- 
fold division of the Paleocene on the basis of its planktonic Foraminifera is proposed, and the 
position of the Paleocene-Lower Eocene boundary is suggested. 

I. ACKNOWLEDGEMENTS 

The writer wishes to express his gratitude to Professor Alan Wood and to Dr. John 
Haynes of the Department of Geology, U.C.W., Aberystwyth, for their guidance, 
stimulating discussions and help, and for reading the manuscript. He is also 
indebted to Professor M. I. Youssef of the Department of Geology, Ain Shams 
University, Cairo, for his valuable discussions, encouragement, and help in the field, 
and to Dr. C. G. Adams of the British Museum (Natural History), London, for making 
available most of the Upper Cretaceous-Lower Tertiary foraminiferal collections of 
the Museum and for his critical reading of the manuscript. 

Grateful acknowledgement is made to the authorities of U.C.W., Aberystwyth, 
for a grant towards the cost of preparation of the plates in this work. 

Sincere thanks are also due to all those who generously forwarded their materials 
and publications, helped in the field, or made available foraminiferal collections in 
their charge. The author would like to mention : Dr. H. L. Abbass, Dr. F. T. 
Banner, Dr. R. W. Barker, Dr. F. T. Barr, Dr. W. A. Berggren, Prof. P. J. Bermudez, 
Prof. F. Bettenstaedt, Dr. E. Bieda, Dr. G. Bignot, Dr. W. H. Blow, Dr. H. M. Bolli, 
Dr. P. Bronnimann, Dr. Y. Le Calvez, Dr. A. A. Castanares, Prof. M. B. Cita, Dr. D. 
K. Clark, Dr. P. Corminboeuf, Prof. M. Crusafont-Pairo, Mr. D. Curry, Prof. J. 
Cuvillier, Mr. F. Dalbiez, Dr. R. Damotte, Dr. C. W. Drooger, Dr. H. S. Edgell, 
Dr. L. Feugueur, Dr. R. Gandolfi, Dr. J. J. Graham, Mr. M. Gulinck, Dr. E. L. 
Hamilton, Dr. W. W. Hay, Prof. H. H. Hess, Prof. I. Hessland, Dr. A. von Hille- 
brandt, Dr. H. Hiltermann, Dr. J. E. van Hinte, Dr. J. Hofker, Mr. N. de B. Horni- 
brook, Dr. L. Hottinger, Mr. B. Issawi, Dr. J. A. Jeletzky, Dr. G. Jenkins, Dr. J. 
Klaus, Dr. I. Kiipper, Dr. M. A. Latif, Mr. J. Magne, Mr. G. Malmoustiers, Dr. P. 
Marie, Prof. R. Marliere, Dr. R. K. Olsson, Dr. E. A. Pessagno, Jr., Dr. K. Pozaryska, 
Dr. I. Premoli Silva, Mr. A. Rechiniac, Dr. R. W. Rex, Dr. B. Romein, Dr. J. Rosell- 
Sanuy, Dr. A. Rouvillois, Prof. H. Schaub, Mrs. M. Seronie- Vivien, Prof. L. Sole- 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 7 

Sabaris, Miss M. Veillon, Prof. M. Vigneaux, Dr. J. H. Van Voorthuysen, Dr. L. Weiss 
and Dr. E. Witwicka. 

A special word of thanks also goes to members of the technical staff of the Depart- 
ment of Geology, U.C.W., Aberystwyth, for their invaluable help, and to the staff of 
the various mining companies in the Esna-Idfu region and the local inhabitants for 
their sincere collaboration and genuine hospitality. 

Much is owed to the authorities of the Robertson Research Organization, and its 
Director Dr. R. H. Cummings, for a Post-Doctoral Research Fellowship during part 
of which the type sections of the Upper Cretaceous-Lower Tertiary in Western 
Europe were sampled. 

Finally, the author is deeply indebted to his parents who paid generously for the 
various stages of this research and without whose spiritual and financial support the 
work could never have been carried out. 



II. INTRODUCTION 

Since the later part of the nineteenth century the highly fossiliferous Upper 
Cretaceous and Lower Tertiary rocks of Egypt have been the subject of numerous 
stratigraphical and palaeontological studies. However, no satisfactory classification 
of these rocks was established and their correlation with the type sections in Europe 
proved very difficult. The difficulty has been mainly explained by the fact that the 
rich macrofaunas of these rocks are strictly localized in nature, and can hardly be 
correlated with the faunas of corresponding strata outside the Tethyan region. As 
a result, the limits of the various stages and substages of the Upper Cretaceous and 
Lower Tertiary were differently interpreted by the various authors, and were chosen, 
as stated by Youssef (1957 : 45), " rather arbitrarily, on whatever meagre evidence 
the stratigrapher can collect ". 

Recently, the rich microfossil content of these rocks has been dealt with by many 
authors, but correlation with the type sections still proved very difficult, and the 
stratigraphical boundaries were, once again, differently interpreted. Moreover, the 
discrepancies between zonations based on macrofossils and those based on micro- 
fossils led to further complications, and regrettably no attempt was made to treat 
together the co-existent macro- and micro-faunas. This, added to the world-wide 
problems of Cretaceous-Tertiary stratigraphy, has resulted in the complication of 
the stratigraphical interpretation of this period in Egypt. 

The same problems were faced in trying to analyse the stratigraphy of the Upper 
Cretaceous-Lower Tertiary succession of the Esna-Idfu region. However, the 
accumulation of knowledge during the last twenty-five years has emphasized the 
value of planktonic Foraminifera as guide fossils for stratigraphical zonation, and 
for regional as well as world-wide correlation. In this connection, Loeblich & 
Tappan (19576 : 1109) stated that " Because of their independence of the sea 



S UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

bottom, rapid dispersal by ocean currents, and their ability to select the depth and 
therefore to some extent the temperature they prefer while living, their relatively 
rapid evolutionary development, and their buoyancy which allows further current 
dispersal even after death of the organism, certain planktonic forms supply the best 
available evidence for world-wide correlations ". Thus, in the present study both 
the macrofauna and the co-existent planktonic Foraminifera are identified and are 
used to interpret the stratigraphy of the region. While the macro-fossils were found 
to be restricted in their geographical distribution and only useful for local correlation, 
the planktonic Foraminifera provided a sound basis for the zonation of the succession 
and its correlation with the type sections and with the known planktonic foraminifer- 
al zones elsewhere. Moreover, the stratigraphical ranges of the macrofossils could be 
established in the light of the planktonic foraminiferal zonation, thus ending a long 
controversy about their ranges. 

However, despite the remarkable value of planktonic Foraminifera, the strati- 
graphical and taxonomic confusion surrounding many of the species, has almost 
masked their importance. The rich planktonic foraminiferal populations encount- 
ered in the Upper Cretaceous-Lower Tertiary succession of the Esna-Idfu region have 
helped to clear up this confusion and to establish the morphological characteristics 
and the stratigraphical range of each of these species. This wealth of planktonic 
Foraminifera, which probably marks the succession as the richest ever recorded, 
provided an excellent opportunity for a detailed study of inter- and intraspecific 
variation among large species populations and for a study of the phylogenetic 
relationships between the various forms recorded. The main part of this work is 
therefore devoted to a detailed study of the important members of the planktonic 
Foraminifera, many of which are here described for the first time from Egypt, 
North Africa and the Middle East. 

Location and geological setting of the esna-idfu region. This region lies 
in Upper Egypt between latitudes 24°58'oo" N and 25 ° 2o'oo"N, and longitudes 32 ° 
20 'oo" E and 33 ° 05 '00" E. It includes part of the Nile Valley between the towns of 
Esna and Idfu, and extends eastwards and westwards into the vast deserts on either 
side, covering an area of about 3,200 square kilometres (Text-fig. 1). 

The region is bounded on the west and northwest by the Lower Eocoene limestone 
scarp (El-Sinn) which forms the eastern edge of the famous limestone plateau of the 
Western Desert. On the south and east, it is bounded by the Nubia sandstone 
plateau, which extends in both directions outside the region to the basement complex, 
at a distance of about 75 kms. to the east and about 100 kms. to the south. 

This Nubia sandstone plateau extends into the Esna-Idfu region constituting 
most of its eastern, southeastern and southern parts, dipping gently to the north- 
west to be progressively overlain by the Sibaiya phosphate, the Esna shale and 
finally by the Thebes limestone and calcareous shale. These four main lithological 
units, which are clearly recognizable in the field, together constitute the Upper 
Cretaceous-Lower Tertiary succession of the Esna-Idfu region. They form the main 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 9 

part of the outcrops in the region and are locally unconformably overlain by one or 
more of the much younger deposits of the Pliocene, Pleistocene and Recent, which 
constitute the rest of the outcrops in the region (Text-fig. 3). 




Fig. 1. Map of Egypt. 



io UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Previous work. The Esna-Idfu region has attracted the attention of geologists 
since the earliest days of geological reconnaissance in Egypt, for the following 
reasons : 

i. It is the only locality in the Nile Valley where both the uppermost Cretaceous 
and the basal Tertiary rocks are very well developed and well exposed. 

2. It is the type area of the famous " Esna shale ", an important group of rock 

units which cover vast areas of the surface and subsurface of Egypt, 
representing a relatively long period of time. 

3. It contains the economically important phosphate deposits of the " Sibaiya 

formation ". 

In spite of its geological importance, little has been published about the Esna- 
Idfu region, and most publications deal mainly with the phosphate deposits. How- 
ever, the stratigraphical succession at a few outcrops in the region was described in 
general terms by Zittel (1883), Schweinfurth (1901, 1904), Beadnell (1905), Hume 
(1911), Stromer & Weiler (1930), Cuvillier (1937a, b), Nakkady (19516) and Youssef 
(1954), but no detailed study has ever been attempted. 

After examining the Upper Cretaceous-Lower Tertiary succession of the Western 
Desert Oases, which he collectively related to the Danian, and divided into lower 
Exogrya overwegi beds, middle greenish and ashen-grey paper-like shales, and upper 
chalk with Ananchytes ovata, Zittel (1883) extended his study to the Nile Valley. 
He pointed to the importance of the conspicuously developed oyster limestone bed 
near Idfu which he wrongly regarded as equivalent to the " Exogyra overwegi beds " 
of the Kharga Oasis. He also observed the great thickness of Esna shale underlying 
the Lower Eocene " Operculina limestone " on the right bank of the Nile near Esna, 
and added " If these paper-shales of Esneh correspond with those of Khargeh and 
Dakhel, then the uppermost white Cretaceous limestone with Ananchytes ovata is 
either wanting at Esneh, or does not contain any fossils and cannot thus be distin- 
guished from the petrographically similar Eocene limestone of the Libyan stage. " 
Apparently, Zittel wrongly correlated the shales directly underlying the Lower 
Eocene limestone near Esna with the lower shales underlying the snow-white chalk 
of the Oases. However, as far as is known to the writer, this is the first record of the 
" Esna shale " in the geological literature of Egypt. 

Schweinfurth (1901, 1904) also recorded these paper shales on both banks of the 
Nile at Esna and El-Sharawna, and considered them to be of Eocene age following 
the general belief of his time. However, neither Zittel (1883) nor Schweinfurth 
(1901, 1904) observed any fossils in these shales. 

Beadnell (1905), in a reconnaissance study designed to explain the mutual relation- 
ship of the Cretaceous and Eocene systems (as understood by him), described the 
succession in the desert margins on both sides of the Nile Valley between Aswan and 
Esna in a series of disconnected sections. He briefly described two sections within 
the Esna-Idfu region, the first was measured in the hills about one kilometre 
northeast of Idfu railway station, near the village of El-Atwani, where a succession of 




Flo. 2. Esna-Idfu Region. Topogr.iphic.il Map 




Fig. 3. Esna-Idfu Region. Geological Map. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 




Nubia Sandstone 

and Variegated 

Shale 



BEADNELL (1905) YOUSSEF (1950 



PRESENT STUDY 



cm 1000 10 20 30 40 50 ms 



Vertical scale 

Fig. 4. Correlation of the stratigraphical succession in G. Owaina section as interpreted 
by Beadnell (1905), Youssef (1954) an d by the present study. 



12 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Nubia sandstone and variegated shale, 112 metres thick, is capped by oyster lime- 
stone. The second was the famous Gebel Owaina section, which was later described 
in more detail by Youssef (1954). 

Both Beadnell (1905) and Youssef (1954) considered the succession in Gebel 

Owaina to be conformable throughout. Beadnell stated that " the first fact 

that impresses the observer is the absolute conformity of the succession throughout.", 
and Youssef also stated " The sequence is apparently conformable throughout." 

The descriptions of the succession and the interpretations of the stratigraphy 
given by Beadnell (1905) and by Youssef (1954) are summarized and compared with 
those of the present study in Text-fig. 4. 

Hume (1911) briefly described the succession in the shallow valleys to the east of 
El-Kilabiya village. He considered the strata between the Campanian oyster lime- 
stone and the Lower Eocene nummulitic limestone as belonging to the Danian, 
which he regarded as the uppermost Cretaceous. 

Stromer & Weiler (1930) described the vertebrate remains of both the Nubia 
formation and the overlying phosphate beds of the Mahamid district, and the 
geology of the same district was briefly dealt with by Nakkady (195 lb). In agree- 
ment with previous works, these authors confirmed the Campanian age of both the 
Nubia and the phosphate formations. 

Cuvillier (19370,6) in a very generalized discussion, assigned the shale and the 
intervening chalk succession of both Gebel El-Kilabiya and Gebel El-Sharawna to 
what he collectively described as Maestrichtian-Danian. 

Youssef (1954) described the succession in the Gebel Owaina section, using the 
Foraminifera as well as the macrofossils to interpret the stratigraphy. Although he 
overlooked the distinct break between the Cretaceous and Tertiary rocks and 
considered the Danian (within which he included most of the Paleocene) as the 
youngest stage of the Cretaceous system, his study is the only serious attempt to 
tackle the stratigraphical problems of this section. Youssef did not deal with the 
Nubia sandstone and the phosphate beds which constitute the lowest part of the 
succession, but simply noted that Beadnell (1905) assigned a Campanian age to the 
latter beds. However, he referred the shale section directly overlying the phosphate 
beds to the Maestrichtian, and arbitrarily considered the Maestrichtian-Danian 
boundary to cut through the middle part of his 97 metres thick shale succession 
overlying the Pecten mayereymari marl (see Text-fig. 4). He assigned the upper 
half of this shale section and the overlying chalk bed to the Danian, and referred the 
upper shale section to the Paleocene and the overlying siliceous limestones to the 
Lower Eocene, although he added that a closer study may prove that these lime- 
stones are still of Paleocene age. 

Youssef (1954), following Cuvillier (1934) and Nakkady (1951a) suggested that the 
term Esna shale, as a formation name, should be abandoned to avoid the different 
age significances adhering to the term through long use. However, he added that the 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 13 

" Esna shales ", as a fades name, should be retained and thus proposed the term 

" Esna shale fades ", as an expression of certain lithological and palaeonto- 

logical characters of a part of the stratigraphic column in certain parts of Egypt." 

In all these studies the succession was only briefly described, and the limits of the 
various stages and substages were vaguely defined. As a result the succession was 
wrongly considered to be conformable throughout, and correlation with the type 
sections or the known other sections outside theTethyan region could not be achieved. 
Moreover, no palaeontological study was ever attempted and no geological map of the 
region was published, except for a very small part in the neighbourhood of El-Kab 
which was mapped by Schweinfurth (1904). The latter has only schematically 
shown the distribution of what he described as Campanian, scattered, rolled 
Eocene pebbles, and Pleistocene and Recent. A part of this map was used by 
Nakkady (1951a) where the same mapping units were followed. 

In a recent geological study of the Esna-Idfu region, the present writer mapped 
the area in detail. This mapping which has resulted in the classification of the 
surface rocks into distinct litho- and bio-stratigraphical units, has also proved for the 
first time, the existence of a distinct break between the Maestrichtian and the over- 
lying Paleocene rocks. In spite of repeated emphasis on the absolute conformity of 
the succession by previous workers, a conglomerate with reworked Upper Cretaceous 
macrofossils was clearly observed in the field and a distinct faunal break was proved 
by the study of the macrofauna and the planktonic Foraminifera. The existence of 
such a stratigraphical break in a region where continuous deposition and absolute 
conformity between the Cretaceous and Tertiary systems has been unquestionably 
accepted, throws a new light on the geological history of Egypt during late Creta- 
ceous and early Tertiary time. Moreover, comparison with various Upper Creta- 
ceous-Lower Tertiary sections in Egypt has clearly indicated the existence of 
stratigraphical breaks of varying magnitudes in areas where the succession was 
described as conformable throughout. 

The detailed geology of the region is discussed elsewhere (El-Naggar, in manu.) 
and the main objects of the present investigation can be summarized as follows : 

1. Stratigraphical analysis of the Upper Cretaceous-Lower Tertiary succession 

of the Esna-Idfu region on the basis of its lithology and macrofossil content, 
and correlation with corresponding sections in other parts of Egypt. 

2. Analysis of the succession on the basis of its planktonic Foraminifera ; 

correlation with the planktonic foraminiferal zones in other parts of the 
world, and the establishment of the ranges of the recorded macrofossil 
species in the light of the planktonic foraminiferal zonation. 

3. Detailed systematic study of the planktonic Foraminifera. 

Methods of investigation. The Esna-Idfu region was geologically mapped, 
using topographical sheets, scale 1 : 100,000 and aerial photographs, scale 1 : 40,000. 
As stated above, the detailed geology of the region and the maps are discussed else- 
where and only small scale reproductions of the maps are presented here (Text-figs. 2, 



i ., UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

3) to show the distribution of the various rock units and the location of the sections 
studied. 

Every possible outcrop in the region was carefully examined and sampled ; fossils 
were collected, and lateral as well as vertical variation in the different rock units was 
considered. The succession was first divided, on the basis of its lithology, into five 
formations and eight members (Text-fig. 5) which are clearly distinguished in the 
field. It was then zoned on the basis of the macrofossils in its various units, and was 
correlated with similar successions in other parts of Egypt. However, because of the 
restricted geographical distribution of most of these macrofossils, correlation with 
the type sections or the other known sections outside the Tethyan region could not be 
achieved, and thus the limits of the various stages and substages could not be 
definitely decided. 

To overcome this difficulty, eight main sections, representing the succession in 
different parts of the region (Text-fig. 7) were chosen for the detailed study of 
planktonic Foraminifera. Several other sections were also examined, but being 
mainly composed of the Nubia sandstone and/or the Sibaiya phosphate formations, 
they were either devoid of Foraminifera, or yielded only very rare, indeterminable 
specimens and are not discussed here. 

The sections were measured and sampled in detail, using a tape, a Brunton compass 
and an " Abney-level ". Samples were collected every three metres and every 
metre or even fraction of a metre when necessary (Text-fig. 7). 

About three hundred samples (100 gms. of each) were processed for foraminiferal 
analysis using standard techniques which differed according to the nature of the 
rocks. In each case, the residue was dried and passed through a series of sieves 
(30, 6o, 120 and 200 mesh). 

All the planktonic Foraminifera in each fraction were picked out and examined, 
counts were made and range charts were constructed. However, as the ranges were 
found to conform well in all the studied sections, it was not found necessary to present 
a chart for each section. The ranges on the general charts, here included, represent 
the ranges in the corresponding parts of each of the studied sections. 

Ninety five species and twenty four subspecies of planktonic Foraminifera are 
identified, twenty species and six subspecies of which are new. All members of the 
genera Globotruncana, Globigerina and Globorotalia are described and figured, except 
for a few rare forms which are not figured. All figures are camera lucida drawings 
by the author. Members of the genera Abathomphalus , Rugoglobigerina, Tnnitella 
and Hedbergella are only listed and will be figured and described in a future publi- 
cation. 

Comparison with type material was carried out wherever possible, and in such 
cases it is noted in the remarks on each species. 

All types and figured specimens are in the British Museum (Natural History), 
London ; a duplicate collection is deposited in the Department of Geology, U.C.W., 
Aberystwyth. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 15 

III. STRATIGRAPHY 

A. General Discussion 

The controversy about Upper Cretaceous-Lower Tertiary stratigraphy has. 
probably been one of the most prolonged in the history of geological literature. The 
loose definition of the various stages and substages and their varied interpretation 
by different authors has always made it difficult to establish the true stratigraphical 
relationship between one stage and another, and has led to great confusion. 

A detailed study of the type sections of these stages and substages, with a critical 
analysis of previous literature, is very badly needed to clear up this confusion. 
However, such detail is beyond the scope of the present work, although the author 
has sampled these sections, and the samples as well as the previous literature are 
now being analysed. Nevertheless, it was found necessary to summarise the strati- 
graphical problems of the various stages and substages dealt with here, and the 
classification adopted in the present study, before proceeding to discuss the succession 
in the Esna-Idfu region. 

The present study is mainly concerned with the period from the Upper Campanian 
to the Lower Eocene, and the main points of disagreement about the stratigraphy of 
this period can be summarized as follows : 

1. Where should the Campanian-Maestrichtian boundary be drawn, and what is 

the position of the Maestrichtian in Upper Cretaceous stratigraphy? 

2. Does the Danian represent the uppermost Cretaceous or the basal Tertiary, 

and what is the nature of the Mesozoic-Cainozoic boundary? 

3. What is the stratigraphical position of the Paleocene, and the relationship 

between its various stages and substages? 

4. Where should the Paleocene-Lower Eocene boundary be drawn? 

The Campanian-Maestrichtian Boundary and the position of the 
Maestrichtian in Upper Cretaceous Stratigraphy 

In 1842, d'Orbigny introduced the term " Senonian " in Upper Cretaceous strati- 
graphy to define the geological interval represented by the white chalk around 
" Sens ", southeast of Paris. However, he did not designate a particular type 
section for his Senonian, but simply stated that " Sens " is situated amidst this 
white chalk which is characterized by its fauna. 

Four years later, Desor (1846) introduced the term " Danian " to describe the 
succession of the Cerithium, bryozoan, coralline and coccolithic limestones which 
disconformably overlie the Senonian white chalk of Denmark and which he had 
previously observed at " Laversines " and " Vigny " in the Paris Basin. He 
considered the Danian as the youngest stage of the Cretaceou system, and the same 
concept was automatically followed by most stratigraphers. 

In 1849, Dumont introduced the term " Maestrichtian " to describe the " calcaire 
grossier " exploited at the quarries of Maestricht 1 in southern Limbourg, Holland, 

1 Dumont's original French spelling of Maestricht is used throughout this work. 



16 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

which he wrongly equated with the " Tuffeau de Ciply " and the limestone of 
' Folx-les-Caves " in Belgium, and correlated with the " calcaire pisolithique " of 
the Paris Basin, which Desor had previously correlated with his Danian. 

A year later, d'Orbigny (1850) described the characteristic fauna of his Senonian, 
including the Maestrichtian of Dumont as the upper part of this stage. 

D'Orbigny (1852) recognised seven stages in the Cretaceous system, all of which 
except the first and last, were established by him. They are, from the base upwards : 
Neocomian, Aptian, Albian, Cenomanian, Turanian, Senonian, and Danian. These 
stages have since been generally accepted by most stratigraphers, in spite of disagree- 
ments and controversies regarding their limits. 

While d'Orbigny regarded the Senonian as comprising the succession of strata 
between the uppermost Turanian and the basal Danian, Hebert (1875) excluded the 
Maestrichtian of Dumont, considering it to range into the Danian, and Haug (1908- 
n) included the Danian of Desor within the Senonian. 

Coquand (1857) divided the Senonian into four substages which he named from 
the base upwards : Coniacian, Santonian, Campanian and Dordonian. However, 
de Grossouvre (1897, 1901) considered the Dordonian to be a junior synonym of the 
Maestrichtian of Dumont (1849) and included the latter within the Campanian as its 
uppermost part. He also subdivided the Campanian (in his sense), on the basis 
of ammonifies, into four successive zones which he named from the base upwards : 
the Placenticeras bidorsatum Zone, the Taxanites delawarense Zone, the Hoplito- 
placenticeras vari Zone and the Pachydiscus neubergicus Zone. On the other hand, 
Arnaud (1897) showed that the ammonite fauna of the type Dordonian (the Pachy- 
discus neubergicus Zone of de Grossouvre) is quite distinct from that of the Campan- 
ian, and should be considered separately. However, in agreement with de Gross- 
ouvre, he regarded the Dordonian as a junior synonym of the Maestrichtian thus 
considering the Senonian stage to include the four substages : Coniacian, Santonian, 
Campanian and Maestrichtian. This classification was followed by most authors, 
although the limits between the various substages, especially those of the Campanian 
and the Maestrichtian, have been largely disputed and mostly unsettled. This has 
been mainly explained by the fact that the original definition of the Maestrichtian 
by Dumont (1849) was rather vague and ambiguous and thus its lower limit has been 
always chosen arbitrarily by the different authors. Again, while in fact no definite 
Maestrichtian deposits have yet been described in the Paris Basin, Dumont wrongly 
correlated the Maestricht chalk tuff with the so-called " pisolitic limestone " of 
Laversines and Vigny, which further complicated the problem. Moreover, de 
Grossouvre (1897, 1901) on the one hand, included the Maestrichtian within the 
Campanian as its uppermost part, and Haug (1908, 1911) on the other, extended the 
Maestrichtian downwards in the succession to include the uppermost part of the 
Campanian at its base. As a result, Haug attached the chalk with Belemnitella 
mucronata to the Maestrichtian, and thus considered the Meudon Chalk of the Paris 
Basin, and the " chalk of d'Obourg ", the " Nouvelles chalk ", the " Spiennes 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 17 

chalk " and the " phosphatic chalk of Ciply ", in Belgium to be of Maestrichtian 
age. To justify this, he subdivided the Upper Campanian Hoplitoplacenticeras vari 
Zone of de Grossouvre into a lower zone with Hoplitoplacenticeras vari which he 
considered to be of Upper Campanian age, and an upper zone with Bostrychoceras 
polyplocum which he attached to the Maestrichtian. Therefore, he considered the 
Maestrichtian (in his sense) as comprising two ammonite zones, an upper with 
Pachydiscus neubergicus ( =Maestrichtian) and a lower with Bostrychoceras poly- 
plocum (=uppermost Campanian), although the latter species has never been 
recorded in the type Maestrichtian or in its junior synonym, the Dordonian. 

This downward extension of the Maestrichtian as suggested by Haug was followed 
by Spath (1926), Laffitte (1934. J 939)> Marie ( I 937. I 943)> Gignoux (1943, 1950), 
Muller & Schenck (1943) and Mikhailov (1947, 1948) as well as many other authors, 
and has confused the position of the Campanian-Maestrichtian boundary. 

On the other hand, Cornet & Briart (1874), followed by Umbgrove (1925, 1926), 
Withers (1935), Bubnoff (1935), Van der Heide (1954), etc. restricted the Maestrich- 
tian stage to the Maestricht tuff and its equivalents only, but this did not solve the 
problem of the Campanian-Maestrichtian boundary. To overcome this difficulty, 
Leriche (1927, 1929), quite justifiably, included in the Maestrichtian, all Upper 
Cretaceous strata in the type area of Dumont, which are older than the Danian of 
Desor (1846) and younger than the Senonian of d'Orbigny (1842) and the Campanian 
of Coquand (1857). This concept, which clearly signifies that no equivalents of the 
Maestrichtian occur in the type Senonian of d'Orbigny, created a tendency among 
various authors to regard the Maestrichtian separately from the Senonian. This has 
been substantiated by the fact that Schijfsma (1946) considered the Foraminifera of 
the Belemnitella mucronata chalk of the Paris Basin, which represents the upper part 
of d'Orbigny's Senonian, to be of Middle and Upper Campanian age, and thus he 
denied the presence of Maestrichtian in the Paris Basin, although Marie (1943) 
considered the Meudon Chalk to be of Maestrichtian age. 

Visser (1951) studied the Foraminifera of the type " Maestricht tuffaceous chalk ", 
reviewing previous studies and discussing the various usages of the term Maestricht- 
ian. She mentioned that while Gignoux (1936-1950), followed by most French 
stratigraphers, had equated the Maestrichtian with the Belemnitella mucronata Zone, 
Muller & Schenck (1943) equated it with the B. lanceolata Zone, restricting the 
mucronata Zone to the Campanian, and Brotzen (1936) considered the mucronata 
Zone to be younger than the Maestrichtian. On the other hand Schijfsma (1946) 
considered the B. mucronata Zone to represent both the Upper Campanian and the 
Maestrichtian, while he considered the Middle Campanian to be represented by a 
particular horizon in which both B. mucronata and Goniatheutis quadrata occur, and 
the Lower Campanian to be represented by the G. quadrata Zone only. She also 
mentioned that while in Belgium and Holland the term Maestrichtian s.s. is generally 
used to describe both the Maestricht tuffaceous chalk and the Kunrade chalk, the 
term Maestrichtian s.l. (or the Maestrichtian as understood by French authors) 
includes the underlying Gulpen chalk as well. Following Schijfsma (1946), she 



[8 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

considered the oldest Cretaceous outcrops in Limburg (the Heervian and the Aachen 
sands) as belonging to the Middle Campanian. However, as her study was mainly 
concerned with the Maestricht tuffaceous chalk, she could not precisely define the 
lower boundary of the Maestrichtian. 

Jeletsky (1951), following Leriche (1927, 1929) and Schijfsma (1946) considered 

the Maestrichtian as " an independent stage younger than and equal in rank 

to the Senonian stage ....", while he considered the Campanian as the upper 
substage of the Senonian. He stated that " The latest research of Abrard (1931 
pp. 24-5 ; 1948 pp. 231, 233, 279-280) has, indeed, shown that at the type locality 
of the Campanian stage in southwest France, near Champagne, the beds with 

Bostrychoceras polyplocum (Roemer) , were originally included in upper 

Campanian and not in lowermost Dordonian (an invalid synonym of Maestrichtian) ". 

Jeletzky's proposition was questioned by Van der Heide (1954) because it meant a 
slight change of the Maestrichtian as originally defined by Dumont (1849). However, 
as previously mentioned by Romein (1961, y e Colloque European de Micropaleontol- 
ogie, Pays-Bas et Belgique, Guide d'Excursions, B. Upper Cretaceous, Limbourg : 
1-3) the confusion and ambiguity of Dumont's definition of the term Maestrichtian, 
led to the fact that the term has evolved through the times, independently from the 
original definition of the type locality. The succession in the type area which is 
known under the names of the tuffaceous limestone of Maestricht (Ma-Md) and the 
Gulpen chalk (Cr 4 ) is generally considered to be of Upper Maestrichtian age (Meyer 
1959 and Voigt i960). However, Romein (1962) extended the Maestrichtian in its 
type area downwards to include most of the Gulpen chalk [Cr 3b (in part) — Cr 4 ], and 
the Maestricht chalk (Ma-Me) which he partly equated with the Kunrade chalk. 

In 1959, the "Congres des Societes Savantes de Paris et des Departements" held at 
Dijon, discussed the stratigraphical and palaeontological problems of the Upper 
Cretaceous in France " Colloque sur le Cretace Superieur Francais ". In spite of 
numerous disagreements, the congress came to the folio-wing conclusions : 

1. The Bostrychoceras polyplocum Zone which has always been assigned to the 

Lower Maestrichtian, is considered to be of Upper Campanian age. 

2. The Maestrichtian is limited to the zone of F 'achy 'discus neubergicus. 

3. Although strictly speaking the Maestrichtian should be excluded from the 

Senonian, it is generally admitted in France that the Upper Senonian 
includes both the Campanain and the Maestrichtian ; being more practic- 
able the committee proposed to continue this usage. 

However, until the type sections of the Senonian and Maestrichtian are studied in 
detail and correlated more precisely, it is advisable to treat the Maestrichtian 
separately from the Senonian. Thus in the present study, the Maestrichtian is 
considered as an independent stage, younger than, and equal in rank to, the Senonian 
stage as suggested by Jeletzky (1951), although it is clearly understood that the time 
span represented by the Maestrictian is much shorter than that of the Senonian. 
Again, the zone of Bostrycoceras polyplocum and its associated fauna which has been 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 19 

wrongly considered to mark the base of the Maestrichtian, is here assigned to the 
Upper Campanian, as the species, although rare in the Aquitaine Basin in general, 
has been recorded in the type Campanian only (Jeletzky 1951 and Mrs. M. Seronie- 
Vivien, personal communication). Moreover, in spite of the accumulated indisput- 
able evidence for the Upper Cretaceous age of the type Maestrichtian, Hofker, in 
several publications (1955-62), has argued for the time-stratigraphic equivalency of 
the type Maestrichtian and the type Danian. Hofker's claims were discussed by 
Loeblich & Tappan (1957ft) and Berggren (1962) who showed clearly that the true 
stratigraphical relationship between the Danian and the Maestrichtian stages is one 
of superposition and not lateral equivalence. 

Stratigraphical Position of the Danian 

Desor (1846) introduced the Danian as the youngest stage of the Cretaceous 
system, typified by the succession of the Cerithhim, bryozoan, coralline and cocco- 
lithic limestones, which disconformably overlies the Senonian white chalk of Denmark. 
He considered these Danian deposits as equivalent to the so-called " pisolitic lime- 
stone " which similarly overlies the Senonian white chalk disconformably at Laver- 
sines and Vigny in the Paris Basin, and which were generally considered, at that 
time, to be of Upper Cretaceous age. In his definition of this new stage he stated : 
" M. Desor pense des lors qu'il faut envisager le calcaire de Faxoe, la craie corallienne 
et le lambeau pisolithique de Laversine et de Vigny, comme un etage particulier de la 
craie, le plus recent de tous, ainsi que l'avait propose M. Elie de Beaumont ; mais il 
ne saurait y comprendre les terrains a Nummulites, qu'il envisage comme etant d'une 
epoque plus recente. M. Desor propose d'appeler cet etage terrain danien, parce 
qu'il est surtout developpe dans les iles du Danemark. Ainsi que l'avait propose 
M. Graves, il est probable qu'on devra y rapporter par la suite le terrain de Maes- 
tricht ". 

Six years later, d'Orbigny (1852) described the fauna of the type Danian, and in 
agreement with Desor, he considered it as the youngest stage of the Cretaceous 
system, but clearly distinguished it from the underlying Maestrichtian. Since then 
the same concept has been automatically followed by most stratigraphers, in spite 
of the doubts about the true Cretaceous nature of the type Danian fauna. Indeed, 
the Tertiary affinities of this fauna have been pointed out as early as 1823 by Forch- 
hammer, (see Rosenkrantz i960), long before the establishment of the term, and 
later by Starkie Gardner (1884) and a few other authors. 

On the other hand, Desor, in his original definition of the term, mentioned that the 
beds of Maestricht may possibly be included within his Danian stage. This vague 
statement led various authors to extend the Danian downwards in the succession 
to include the Maestrichtian and even the Campanian, in spite of the marked strati- 
graphical break between the Danian and the underlying strata in both the type 
region of Desor and in other parts of the world. Thus, Mayer-Eymar (1872) consid- 
ered the Danian to include the Campanian of Coquand, the Maestrichtian of Dumont 
and the Danian of Desor, while Hebert (1875) extended the Danian downwards to 



20 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFER A 

include the Maestrichtian rocks only. On the other hand Munier-Chalmas & de 
Lapparant (1893) distinguished the Danian from the Maestrichtian, but extended 
the former upwards in the section to include the Montian as its upper substage and 
the typical Danian as its lower, including them both in the Cretaceous system. 
Again, Geikie (1903) considered the Danian to include the Maestrichtian as its 
lower part and the Montian as its upper, while Denizot (1936) considered the Mae- 
strichtian to be distinct from the Danian, although he included it as a substage of the 
latter. 

This arbitrary use of the term Danian, resulted in the fact that the literature is 
now filled with a considerable amount of wrong and confused information which led 
to the vagueness and ambiguity of the term, and made it difficult to decide its true 
stratigraphical position. 

However, de Grossouvre (1897, 1901) considered both the Danian and the Montian 
as a single unit in the basal Tertiary. He reasoned that as the Danian is devoid of 
the index fossils which characterise the Cretaceous rocks below, such as the ammon- 
ites, belemnites, inocerami, trigonias, rudists (Hippurites, Spherolites and Radio- 
lites), etc., the Cretaceous-Tertiary boundary should be drawn at the base of the 
Danian. Unfortunately, this valuable remark was received with little enthusiasm, 
and most stratigraphers continued to use the term Danian in the sense of Desor 
(1846) and d'Orbigny (1852), as the youngest stage of the Cretaceous system. 

Nevertheless, this logical explanation of the Cretaceous-Tertiary boundary 
suggested by de Grossouvre, has started, since the early days of this century, to gain 
the support of a few geologists, e.g. Brunnich-Nielsen (1920), Rosenkrantz (1920), 
Harder (1922), Kayser (1924), Keller (1946), and Morozova (1939), who clearly 
demonstrated the Tertiary affinities of the Danian fauna and thus advocated its 
position at the base of the Tertiary. 

Although faced with strong opposition and neglect at that time, this proposition 
has recently received overwhelming support by a great number of stratigraphers, 
e.g. Jeletzky (1951-1962) Bronnimann (1953), Troelson (1957), Loeblich & Tappan 
(1957a, b), Bolli (19576), Nakkady (1957), Bolli & Cita (1960a, b), Hay (i960), Lys 
(i960), Reyment (1960a, 6) Burollet & Magnier (i960), Rosenkranz (i960) and 
Berggren (19606, 1962). These recent studies have shown that the Danian, in its 
type region and in various parts of the world is separated from the Maestrichtian 
rocks below by a distinct faunal break which is generally accompanied by a physical 
break of varying magnitude. The pronounced nature of this break and its world- 
wide extent clearly mark the Maestrichtian-Danian boundary as the natural bound- 
ary between the Mesozoic and the Cainozoic eras, and justifies the position of the 
Danian at the base of the Tertiary system. At the Maestrichtian-Danian boundary, 
all the Globotruncana, Rugoglobigerina, Trinitella, Plummerita, Abathomphalus, 
Hedbergella, Globigerinelloides, Schackoina, Pseudotextularia, Pseudognembelina, 
Gublerina, Planoglobulina, Racemiguembelina, and Heterohelix, among a large number 
of microfossils ; all the ammonites, the true belemnites (Belemnitellidae), rudists, 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 21 

inocerami (?) ; all the mosasaurs, plesiosaurs, ichthyosaurs ; all the dinosaurs and 
pterodactyls, etc. were found to die out completely and to be replaced in the over- 
lying Danian by a different fauna where Globigerina, Globigerinoides, Globorotalia, 
Chiloguembelina, typical Tertiary molluscan and echinoderm fauna, and primitive 
placental mammals made their appearance for the first time. This geologically 
abrupt extinction of several typical representatives of Mesozoic life at the Maestricht- 
ian-Danian boundary, which is followed by an equally abrupt appearance of definite 
Cainozoic forms in the Danian rocks above, and which is documented in both the 
marine and non-marine domains, clearly marks this boundary as the major biochrono- 
logical line between the Mesozoic and the Cainozoic Eras. This is substantiated by 
the fact that this major break is also accompanied by a pronounced change in the 
generic and specific composition of many other groups such as the molluscs (Rosen- 
krantz i960), the echinoderms (Poslavskaya & Moskvin i960), the coccolithophorids 
(Bramlette & Sullivan 1961), as well as by a physical break of varying magnitude and 
world-wide extent. On the other hand, many other species and genera survived this 
change and continued their development from the Maestrichtian into the Danian or 
even later stages. These were used by various authors as an argument for the 
Cretaceous and/or the transitional character of the Danian fauna, and hence their 
preference to include the Danian within the Cretaceous system. However, this does 
not minimize the importance of the distinct stratigraphical break between the 
Maestrichtian and the Danian, as survival of certain members of the organic life 
across similar major faunal breaks is reasonably understood and clearly documented 
in the history of the earth. Moreover, contrary to Brotzen (1959), the faunal break 
between the Maestrichtian and the overlying Danian is definitely much more 
pronounced and widespread than any known breaks between the Danian and the 
overlying stages, or between the Maestrichtian and the underlying stages. Therefore, 
the Mesozoic-Cainozoic contact is naturally placed at this boundary which is, as 
described by Jeletzky (1962), " a natural boundary based on a unique and easily 
recognizable, major biochronological event apparently reflecting some kind of a 
radical, world-wide change in the physical regime of our planet ". 

Thus in the present study, the Danian is considered as the oldest stage of the 
Tertiary system, and the Maestrichtian-Danian contact is taken to mark the 
Mesozoic-Cainozoic boundary. This is in spite of the fact that various authors (e.g. 
Brotzen 1959 and Yanshin i960) have strongly argued for, and continued to use the 
term Danian in the sense of Desor, as the youngest stage of the Cretaceous system. 
However, neither of these authors could provide any evidence against the definite 
Tertiary character of the Danian fauna or the marked faunal break between the 
Maestrichtian and the overlying Danian. Brotzen simply stated " To range the 
Danian with the Cretaceous or the Tertiary is only a question of convention ", and 
unjustifiably added " In my opinion no fundamental evidence has been adduced 
which will necessitate changing the classical range of the Danian as the youngest 
stage of the Cretaceous to the oldest stage of the Tertiary ". Yanshin built his 
argument on a completely unsound basis and his paper is full of confusion and numer- 
ous mistakes in matters of fundamental importance. 



22 upper cretaceous-lower tertiary for aminifer a 

Nature of the Mesozoic-Cainozoic Boundary 

The traditional usage of the Danian as the youngest stage of the Cretaceous 
system instead of its true position at the base of the Tertiary, has always concealed 
the nature of the Mesozoic-Cainozoic boundary which in most parts of the world is 
marked by a distinct stratigraphcial break. 

In addition to the indisputable, major faunal break between the Maestrichtian 
and the overlying Danian, the latter was found, in various parts of the world, to be 
separated from the Cretaceous rocks below by physical breaks of varying magnitude. 
In places, where the Upper Cretaceous-Lower Tertiary succession was described to 
be conformable throughout, (e.g. Egypt), unconformities and disconformities are 
being discovered with further detailed examination of the previously described 
sections (e.g. Farafra, Dakhla and Kharga Oases and the Esna-Idfu region). In 
places where the lithology on either side of the contact does not permit the detection 
of the physical break, the abrupt extinction of numerous, diverse representatives of 
Cretaceous life, and the sudden appearance of new Tertiary forms, clearly mark the 
Mesozoic-Cainozoic contact. 

Although evident and clearly documented, such a distinct, sharp and world-wide 
break at the Maestrichtian-Danian boundary, represents one of the most enigmatic 
problems in the history of the Earth. It is beyond the scope of the present work to 
try to explain it, but it clearly points to the fact that the life record between the 
uppermost Maestrichtian and the lowermost Danian, as we know it, is incomplete 
and may possibly be sought for in the deep oceanic troughs, or in yet undescribed 
sections, where a complete Cretaceous-Tertiary sequence may be found. Moreover 
it reflects, as previously mentioned by Jeletzky (1962) " some kind of a radical, 
world-wide change in the physical regime of our planet ", which may be regarded as a 
" catastrophe " or a " revolution ", and which still awaits further explanation. 

Stratigraphical Position and Classification of the Paleocene 

Schimper (1874) introduced the term Paleocene to distinguish the lowest part of 
the Tertiary system, which was then included at the base of the Eocene. He used 
this term to describe the " Travertin de Sezanne " in the eastern part of the Paris 
Basin, which he considered on the basis of its floral content to be worthy of distinc- 
tion from both the younger Eocene and the older Upper Cretaceous series. The 
conglomerates of " Meudon " and " Cernay " which are characterized by their 
mammalian fauna were also attached to the Paleocene and were found to mark the 
limits of a sedimentary cycle which followed the Cretaceous chalk and preceded the 
" Nummulitic transgression ". 

Thus the Paleocene was generally considered to represent one sedimentary cycle 
spanning the time between the uppermost Cretaceous and the basal Eocene, although 
the controversy about the true position of these two boundaries made it difficult to 
establish the boundaries of the Paleocene series. For example, the so called " piso- 
litic limestone " of Laversines and Vigny and its equivalents, in the Paris Basin 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 23 

which represent the first marine transgression over the truncated surface of the 
Upper Cretaceous Chalk, were repeatedly assigned to the Campanian, Maestrichtian 
or Danian. As a result, these beds were generally excluded from the Paleocene, 
although they have been recently proved to be of definite basal Tertiary age and 
correlated with the " Tuffeau de Ciply " of Belgium (Damotte & Feugueur 1963). 
Similarly the lagoonal, clayey and lignitic deposits which lie between the " Cernay 
conglomerate " or its equivalents and the base of the Cuisian, were included by some 
authors within the Paleocene, while others placed them at the base of the Eocene. 
Therefore, the Paleocene in the Paris Basin was very poorly defined and was generally 
taken to include various rock units between the Upper Cretaceous and the basal 
Eocene such as the " Tuffeau de la Fere " and the " Argile de Vaux-sous-Laon " ; 
the " Sables de Bracheux et de Chalons-sur-Vesle " ; the " Travertin de Sezanne " ; 
the " Calcaire de Rilly " and the " Conglomerat de Cernay ", and by some authors 
the " Argile plastique " and the " Lignites du Soissonnais " as well, but its lowermost 
and uppermost limits remained uncertain. Moreover, the fact that the Paleocene, 
as defined above, in its type region, is represented by non-marine and very near- 
shore deposits which were mainly zoned on the basis of their floral and mammalian 
contents, made any correlation with the corresponding marine deposits practically 
impossible. The shallow water marine fauna of the " Sables de Bracheux " and its 
equivalents, which were described by Farchad (1936) and Rouvillois (i960) proved 
to be largely of a localized nature and hence, of little value in correlation. 

As a result, various authors, e.g. Mangin (1957), suggested that the term Paleocene 
should be dropped altogether and the Eocene be extended downwards (as it was 
originally defined) to include at its base the youngest Lower Tertiary formations. 
However, the fact that the Paleocene, in its type region and in other parts of the 
world is generally represented by a particular sedimentary cycle and/or biological 
unit, distinguished from that of the overlying Eocene, favours its separate treatment. 

On the other hand, long before the introduction of the term Paleocene, several 
stages had been established to describe various segments of the succession represent- 
ing the time span between the uppermost Cretaceous and the basal Eocene, e.g. the 
Landenian (1839), the Heersian (1851), the Montian (1868) and the Thanetian (1873). 
In addition various stages were introduced later, e.g. the Sparnacian (1877), the 
Seelandian (1924) and the Ilerdian (i960). Moreover, the Danian which was 
wrongly introduced (1846) as the youngest stage of the Cretaceous system, was 
proved, as stated above, to represent the oldest stage of the Tertiary, and is thus 
included as the lowest stage of the Paleocene series. However, as these type sections 
are widely spaced, were designated by different authors, and are represented by 
different facies (continental, lagoonal, shallow- water and deep-water marine deposits), 
it became difficult to establish the true stratigraphical relationship between one 
stage and the other, and between each stage and the corresponding part in the type 
area of the Paleocene. Nevertheless, to avoid the difficulty of correlation with the 
peculiar facies of the type Paleocene in the Paris Basin, different authors tended to 
use various sets of the above-mentioned stage names to represent the basal Tertiary, 



24 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

as subdivisions of the Paleocene, or within the basal part of the Lower Eocene. 
Moreover, they tried to introduce these stage names to the type Paleocene, but the 
relationship between one stage and the other was not clearly understood, and was 
arbitrarily interpreted by the individuals concerned. Thus, while the Paleocene in the 
Paris Basin was regarded as including the Thanetian and Sparnacian ; the Montian, 
Thanetian and Sparnacian ; the Montian and Thanetian ; or the Thanetian alone, 
it was taken to include the Montain and Landenian in southern Belgium ; the 
Montian, Heersian (with or without the Infra-Heersian) and Landenian in north- 
eastern Belgium and in Holland ; the Thanetian, with or without the Woolwich and 
Reading Beds in England ; the Seelandian, Thanetian and Landenian in Sweden and 
Denmark, and any further combination of these, plus or minus the Danian. More- 
over, because of the confusion about the true chronological relationship between the 
Danian and the Montian, Sigal (1949), followed by most Mediterranean geologists, 
introduced the Dano-Montian as a new term to cover the early Paleocene period. 

However, in his study of the basal Tertiary in the Franco-Belgian Basin, Feugueur 
(1955, 1962, 1963) included the Paleocene within the Lower Eocene and equated the 
Cuisian with the Upper Ypresian, the Sparnacian with the Lower Ypresian, and the 
Thanetian of the Paris Basin with the Landenian of Belgium, although he pointed out 
the fact that the Lower Landenian (=Heersian) is missing in the Paris Basin. 
Feugueur followed Leriche (1903) who had previously recognized in the Landenian 
a marine lower division and a continental upper one, and divided the marine Lower 
Landenian, on the basis of its shallow water molluscs, into three zones, from the 
base upwards: the Arctica morrisi Zone, the Pholadomya oblitterata Zone and the 
Arctica Scutellaria Zone. However, Feugueur considered the latter zone to be of 
lagoonal, rather than of marine origin and attached it to the overlying Upper Land- 
enian, which he regarded as comprising the lagoonal Arctica Scutellaria Zone at its 
base and the continental Physa gigantea Zone on top. On the other hand, while 
Feugueur equated the so-called " Thanetian of the Paris Basin " with the Landenian 
of Belgium, and noted that the basal Landenian (= Heersian = A rctica morrisi Zone) 
is missing in the Paris Basin, Arctica morrisi was found to mark the top of the 
Thanetian in England. In spite of this fact, the so-called Thanetian in the Paris 
Basin has always been equated with the Thanetian of England, which is apparently 
much older. Thus, despite the value of Feugueur's correlation in the Anglo-Franco- 
Belgian basin, several problems in the same basin were left unexplained. The 
relationship between the Thanetian of England and the Thanetian of the Paris 
Basin ; the Thanetian of England and the Landenian of Belgium ; the Thanetian, 
the Landenian and the Montian ; the Montian and the Danian ; the Danian and the 
Heersian ; and the Heersian and the Montian are still not clear. Moreover, the 
relationships of the other type stages of the Paleocene outside the " Anglo-Franco- 
Belgian Basin " to each other and to those in the basin were left unsolved. It is not 
really understood what sort of chronological relationship exists between the Danian 
and Montian, the Montian and Seelandian, the Montian and Landenian, the Thanetian 
and Landenian, the Montian, Thanetian, Landenian and the Ilerdian, in their 
respective type areas. Nevertheless, selected sets of these stage names were 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 25 

arbitrarily used by various authors to represent the Paleocene, but were differently 
interpreted and much confused. 

Loeblich & Tappan (1957a, b) divided the Paleocene into a lower and an upper 
stage which they equated with the Danian and Landenian respectively. They 
(1957a) suggested the inclusion of the Thanetian as the lower substage of the Landen- 
ian and the Sparnacian as the upper one, although they mentioned (1957&) that the 
Sparnacian may represent both late Paloecene and early Eocene time. These 
authors recorded the occurrence of G. daubjergensis Bronnimann and G. triloculi- 
noides Plummer in the lower part of the type Montian (the " Tuffeau de Ciply "), 
and thus considered the type Montian as the lateral equivalent of the type Danian, 
and stated " The occurrence of the Cerithium fauna in the type Danian, and the 
Nautilus danicus in Montian equivalents, the species of the daubjergensis-compressa 
faunal zone represented in both type Danian and type Montian and their equivalents 
over the world, the identical stratigraphic position of the Danian and Montian, each 
unconformable on the Cretaceous, and underlying the Landenian sediments, and the 
fact that they are never found together, leads inescapably to the conclusion that the 
Danian and Montian are merely different lithologic and faunal facies of identical 
geologic age. We suggest that the term Danian be used to include the Montian 
also, inasmuch as the type Danian includes beds of both facies. The Danian should 
be used as a stage name within the Paleocene ". 

Loeblich & Tappan's proposition was previously mentioned by de Grossouvre 
(1897) and Harder (1922), and is followed by a number of authors, in spite of the fact 
that Vincent (1928), Ravn (1933), Chavan (1946), Marie (i95o),Hofker (1961a, 1962a), 
Moskvin & Naidin (i960) and Voigt (i960) have strongly emphasized the fact that 
the type Montian is younger than the type Danian. 

Hofker (1961a) recorded the occurrence of Globorotalia pseudomenardii Bolli, 
Globorotalia ehrenbergi Bolli and Globorotalia pusilla laevigata Bolli in the lower part 
of the type Montian (the " Tuffeau de Ciply "), and thus correlated the Montian with 
the Globorotalia pusilla pusilla and the Globorotalia pseudomenardii Zones of Bolli 
(1957&). On these grounds, he considered the Montian to be of Middle Paleocene 
age and introduced what he described as the Lower Paleocene between the Danian 
and the Montian, correlating it with the Seelandian of Brotzen (1948), and stating 
that " Alors, il n'y a plus de doute : le Montien-type, vers sa base, est deja du 
Paleocene moyen et il est impossible de paralleliser le Montien avec le Danien ; 
il y a un etage entier entre le Danien et le Montien, represents par le Tuffeau glau- 
conieux, qui, deja est du Paleocene, comparable aux couches plus basses du ' Lizard 
Springs formation du Trinidad ' ". Moreover, he added that the benthonic Fora- 
minifera of the " Calcaire grassier de Mons ", which forms the upper part of the type 
Montian, leaves no doubt about its Upper Paleocene age, although the planktonic 
Foraminifera are very rare and do not form a typical association. He further 
complicated the problem by considering the Montian as the upper part of the Lower 
Paleocene and the G. trinidadensis-G. uncinata Zones of Bolli as representing the 
lower part of this Lower Paleocene, which overlies the Danian. Again, he stated that 



26 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

the Landenian overlies the Montian, and that it contains in its lower part a benthonic 
foraminiferal fauna comparable to that of the Thanetian of England, but with no 
pelagic forms. He did not state to which part of the Paleocene the Thanetian 
belongs if the " Calcaire de Mons " is considered to be of Upper Paleocene age as he 
suggests. 

Thus, in a single paper, Hofker considered the Montian to be equivalent to the 
upper part of the Lower Paleocene, to be Middle Paleocene in age and (as the " Cal- 
caire de Mons ") to be of Upper Paleocene age. However, the existence of G. 
daubjergensis Bronnimann in the " Tuffeau de Ciply ", discovered by Loeblich & 
Tappan (1957ft), confirmed by the present author, by Gartner & Hay (1962) and by 
Berggren (1963), throws doubt on the validity of Hofker's record, especially of G. 
pseadomenardii and G. pusilla pusilla. In the Esna-Idfu region and in other parts 
of the world, the last mentiond species occur at a much higher level in the Paleocene 
succession than the uppermost limit of G. daubjergensis. Moreover, the writer has 
examined washed residues of the " Tuffeau de Ciply" in Dr. Hofker's possession 
and others placed by him in the collection of the Geological Museum at Haarlem 
but could not trace these species, in spite of Hofker's statement that he had found 
them in abundance. On the contrary, in the latter collection, forms such as G. 
trinidadensis Bolli and G. uncinata uncinata Bolli (together with undescribed forms) 
deny the possibility of the existence of G. pseudomenardii in the " Tuffeau de Ciply ". 
The present author has sampled the type "Tuffeau de Ciply ", and the outcrop of 
the " Calcaire de Mons " at the " Trenchee de Hainin " in the Mon's basin. These 
samples together with one from the type " Calcaire de Mons " of the " Puits Goffint " 
and several Montian samples from drilling in the Mons and the Landen Basins, 
kindly provided by Mr. M. Gulinck and Professor R. Marliere, are still under study. 
Until this study is completed no decision can be reached regarding the true strati- 
graphical relationship between the Danian and the Montian. However, authors 
have already divided into three groups ; one advocating the time-stratigraphic 
equivalency of the type Danian and the type Montian ; another claiming a much 
younger age for the Montian and placing it higher in the Paleocene; and a third 
who clearly realizes the close similarity between the Danian and Montian faunas, 
but who still advocates placing the Montian on top of the Danian. 

In support of the latter proposition, Voigt (i960) stated that " Researches now in 
progress of the bryozoa of the Montian in Belgium and Holland show very close 
relationship to the bryozoan fauna of the Danian, however ; a considerable part of 
foreign, in part new, species still leaves a possibility for the lower Montian, the 
" Tuffeau de Ciply ", to be younger than upper Danian." 

In agreement with Voigt (i960) Moskvin & Naidin (i960) recorded the occurrence, 
in southwestern Russia (Crimea, Caucasus and Transcaspian Oblast), of a limestone 
horizon with a molluscan fauna similar to that described from the type Montian, 
directly overlying bryozoan and crinoidal limestone with typical Danian fauna. 
Thus these authors concluded that the time-stratigraphic equivalency of the type 
Danian and the type Montian as suggested by Loeblich & Tappan (1957a, b) is 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 27 

practically impossible. However, because of the close relationship of the fauna, 
they considered the Montian as the upper substage of the Danian as previously 
suggested by Munier-Chalmas & de Lapparent (1893), and divided the Paleocene 
into a lower, Danian and an upper, Thanetian stage. 

On the other hand, Gartner & Hay (1962) recorded the occurrence of a specimen 
closely resembling Globigerina daubjergensis Bronnimann in the " Tuffeau de Ciply ". 
This record is confirmed by the present author, and by Berggren (1963) who recorded 
this species together with Globigerina triloculinoides Plummer and Globorotalia 
pseudobulloides (Plummer) at the base of the same formation. Berggren quoted 
Wienberg-Rassmussen (1962) who considered the " Tuffeau de Ciply ", on the basis 
of its Echinoderm fossil content, to be of definite Danian, and presumably Middle 
Danian age, and concluded that "... the lower Montian (Tuffeau de Ciply) is time- 
equivalent with the lower and middle Danian of Denmark ; the relationship between 
the upper Montian (Calcaire de Mons) and the upper Danian remains uncertain. By 
extrapolation it is probably correlative in part with the upper Danian, and, in part, 
younger than known, exposed Danian in Denmark. It is also possible that sub- 
surface younger Danian in Denmark may fill the missing void in our information 

Loeblich & Tappan (19576), also studied samples from both the type Thanetian 
and the type Sparnacian and stated that no planktonic Foraminifera were found in 
the samples from these sections. They quoted Haynes (1955) who had previously 
recorded Globigerina triloculinoides Plummer, G. pseudobulloides Plummer and 
G. velascoensis (Cushman) aff. var. acuta Toulmin from type Thanetian samples. 
Thus they equated the Thanetian with " the highest Paleocene planktonic faunal 
zone — the Globorotalia velascoensis-acuta Zone ". However, on their correlation 
diagram (1957a, fig. 28) they equated the Sparnacian with this zone, which they 
considered as the upper subzone of their " Landenian " angulata Zone, while they 
regarded the Thanetian as the lower part of this zone, the pseudobulloides Subzone. 

However, examination of Globorotalia velascoensis (Cushman) aff. var. acuta 
(Toulmin) of Haynes (1955, 1956) from the type Thanetian of England, has 
shown that it is a reworked Upper Cretaceous Globotruncana species. The state of 
preservation of the specimen does not allow its specific identification with certainty, 
but the occurrence of reworked Upper Cretaceous species in the type Thanetian was 
mentioned by Haynes (1956), and these species have been studied by Haynes and 
El-Naggar (in press). The same conclusion has been reached independently by 
Berggren & Barr {in Berggren 1963). 

Nevertheless, this record by Haynes (1955, 1956) was used by Loeblich & Tappan 
(1957a, b), Bolli & Cita (i960 a, b), and several other authors as a basis for correlating 
the type Thanetian with the Globorotalia velascoensis Zone of Upper Paleocene age. 
However, examination of several type Thanetian samples has shown that they 
contain a mixture of Senonian and Danian forms. The existence of such forms as 
Globigerina daubjergensis, G. triloculinoides, Globorotalia pseudobulloides, G. trinidad- 
ensis, G. quadrata, which are clearly Danian in age, with forms such as Globotruncana 
cretacea, G. linneiana linneiana, G. fornicata fornicata, G. rosetta rosetta, G. tricarinata 



28 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

tricarinata, and abundant Rugoglobigerina, Hedbergella and Globigerinelloides species, 
which indicate an Upper Senonian, pre-Maestrichtian age, and the entire absence of 
typical Maestrichtian forms, represent one of several enigmatic problems about the 
true stratigraphical position of the Thanetian, and the geological history of England 
during the Cretaceous-Tertiary transition period. The existence of mixed Senonian 
and Danian fauna in the type Thanetian may be explained by the suggestion that the 
whole planktonic foraminiferal content is reworked from previously existing Senonian 
and Danian strata, although no Danian deposits have yet been recorded anywhere in 
the British Isles. This may be substantiated by the record, in the type Thanetian, 
of a meagre calcareous nannoplankton assemblage which also occurs in the " G. 
pseudomenardii Zone of Trinidad " (Bramlette & Sullivan 1961). On the other hand, 
it could suggest that while the Senonian forms are reworked from the underlying 
chalk, the Danian ones are possibly indigenous ; hence the type Thanetian may 
include strata which are equivalent to the type Danian. This conclusion is doubted 
here owing to the absence of a typical Danian macrofauna and fauna of benthonic 
Foraminifera. However, the author refrains at present from taking any decision 
about the true stratigraphical position of the Thanetian until its type sections are 
examined in detail and correlated with the other type sections of the various stages 
of the Paleocene, and with the Paleocene in other parts of the world. Nevertheless, 
the Thanetian of England is probably different from the Thanetian in the Paris Basin ; 
while Arctica morrisi marks the top of the former, it is supposed to underlie the 
latter. This simply points to the fact that the true stratigraphical position of the 
Thanetian, like that of the Montian, is not yet clearly understood and that the vague 
use of these terms in Paleocene stratigraphy is far too dangerous at the moment. 

Loeblich & Tappan (1957ft) also mentioned the difficulty in correlating the Sparna- 
cian, as it is represented in its type section by non-marine facies. However, they 
mentioned that as the non-marine Woolwich and Reading Beds and the underlying 
marine Thanet Beds of England, are considered as deposits of one and the same 
sedimentary cycle (Stamp 1921 ; Haynes 1955), the non-marine type Sparnacian 
is more probably related to the Paleocene. Moreover, they stated that " Until 
marine strata referable to the Sparnacian can be obtained this problem is difficult 
to solve. It may represent both late Palocene and early Eocene time ". However, 
on their correlation diagram they considered the Sparnacian as the upper substage 
of the Landenian, although Feugueur (1955, 1962, 1963) has constantly advocated 
the time-stratigraphic equivalency of the type Sparnacian and the lower Ypresian. 

This brief discussion clearly indicates the great difficulty in correlating the various 
stages and substages of the Paleocene, because of the non-marine, or very near-shore 
facies of most of the type sections, and the uncertainty about their true chronological 
relationship. It also indicates that the assignment of the various planktonic 
foraminiferal zones by Loeblich & Tappan (1957a, b), Bolli (1959), Bolli & Cita 
(1960a, b), Hofker (1961a, 1962a) and various other authors, to the Montian, Thanet- 
ian, Sparnacian, or Landenian, is rather arbitrary and is not based on any proper 
correlation with the type sections. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 29 

To overcome the difficulty of correlating marine and non-marine deposits and the 
uncertainty resulting from such correlation, Hottinger & Schaub (i960) proposed the 
Ilerdian as a new stage to represent the marine Upper Paleocene. These authors 
studied the larger Foraminifera of this new stage and stated that it has no equivalent 
in the Paris Basin, but added " We only know that it is immediately below the 
Cuisian. Very likely it lies between the Cuisian and the marine phase of the Montian. 
So far we had no opportunity to determine whether a part — and in the affirmative 
case, which part — of this stage corresponds with the marine phase of the Landenian." 

Gartner & Hay (1962) studied the planktonic Foraminifera of the type Ilerdian, 
and affirmed its Upper Paleocene age. However, examination of several Ilerdian 
samples from Mont Cayla, kindly presented by Miss M. Toumarkine of the Sorbonne, 
has shown that these deposits are of Lower Eocene, rather than of Paleocene age 
(see discussion under each of the species recorded by Gartner & Hay 1962). This 
throws doubt on Hottinger & Schaub's conclusion, on Gartner & Hay's identifications 
and on the validity of the Ilerdian as a stage of the Paleocene. The use of the term 
Ilerdian in Paleocene stratigraphy is therefore considered inadvisable, especially 
as the relationship of the " Ilerdian " to the other stages and substages of the 
Paleocene is not yet understood. [The type section of the Ilerdian in the Tremp 
basin, as well as several other Ilerdian outcrops in Spain and in France, have been 
sampled in detail by the present author in an attempt to discover their true strati- 
graphical positions.] 

In the present study, the Paleocene is considered to be a distinct series at the base 
of the Tertiary system, older than, and equal in rank to, the Eocene series. It spans 
the time between the top of the Cretaceous and the base of the Eocene, and includes 
the Danian as its lowest stage. The controversy about the chronological and 
stratigraphical relationships of the various stages and substages of the Paleocene 
(other than the Danian) as summarized above, necessitates the temporary abandon- 
ment of these terms and the use of faunal zones instead. The establishment of 
faunal zones which are built on the basis of evident evolutionary trends, and which 
can be correlated in various parts of the world, is the only solution at the moment to 
the numerous problems in Paleocene stratigraphy. Correlation of the type sections 
of the various stages and substages of the Paleocene with these zones is bound to 
show the true stratigraphical relationship between one stage and the other, and will 
lead to the development of a reliable means of correlation for this series. 2 

The present study has shown that in Egypt and elsewhere, the Paleocene is 
divisible into three faunal zones in which the planktonic Foraminifera represent 
a continuous evolutionary sequence showing clearly recognizable trends. Each of 
these zones corresponds to a definite evolutionary stage. They are as follows : 

1. A lower zone marked by the first appearance at its base of the genera Globoro- 
talia and Globigerina, and characterized by an assemblage of Globigerina and globi- 

2 The relationship between these stages has now been clarified and the suggested stage names are 
discussed elsewhere (El-Naggar, in press), and inserted on some of the accompanying figures. 



30 UPPER CRETACEOUS LOWER TERTIARY FORAMINIFERA 

gerina-like, rounded, non-keeled Globorotalia. These globorotalias are generally 
smooth-surfaced, with a tendency towards the development of a slightly roughened 
surface and a gently compressed test upward in the section. This zone is character- 
ized by the presence of Globorotalia pseudobidloides (Plummer), G. trinidadensis 
Bolli, G. compressa (Plummer), Globigerina triloculinoides Plummer and G. daub- 
jergensis Bronnimann among other species, but as both Globorotalia compressa and 
Globigerina daubjergensis are found to die out completely at its top, they are taken as 
the index species of the zone, which is known as the Globorotalia compressa I Globi- 
gerina daubjergensis Zone. The planktonic Foraminifera of this zone characterizes 
the Danian in its type section and the known Danian deposits elsewhere, thus it is 
taken to represent the Danian, or the oldest stage of the Paleocene series. The 
lower limit of this zone marks the Cretaceous-Tertiary contact, and its upper limit is 
marked by the disappearance of its index species and the first appearance of the 
truncated Globorotalia which characterize the following zone. 

2. A middle zone characterized by an assemblage of Globigerina and truncated, 
non-keeled Globorotalia, in addition to the rounded form which first appeared in the 
underlying zone. At the base of this zone, most representatives of the genus 
Globorotalia (generally rounded or slightly compressed in the underlying zone) start 
to become flattened on the dorsal side and strongly protruding on the ventral, with 
the development of an acute axial periphery, but with no keel, or only a partially 
developed, incipient one. Again the tendency towards the development of a rough- 
ened surface, flattening of the dorsal side and the development of a sharply acute 
axial periphery and a partial keel, increases gradually upwards in the section. An 
excellent example of these truncated globorotalias is G. angulata angulata (White) 
which is taken as the index species of this zone, although it continues in the over- 
lying zone. The development of G. angulata angulata from the typically rounded 
form G. pseudobidloides (Plummer) through G. trinidadensis Bolli and G. uncinata 
uncinata Bolli is clearly documented (Text-fig. 15), and demonstrates the tendency 
of Globorotalia to develop from rounded to truncated forms upwards in the section. 
On the other hand, G. angulata angulata also demonstrates the evolutionary develop- 
ment of the truncated, non-keeled Globorotalia into the sharply-keeled ones by the 
development, in the overlying zone, into G. velascoensis velascoensis (Cushman) 
through G. angulata abundocamerata Bolli. This, added to the fact that the first 
appearance of G. angulata angulata coincides with the disappearance of the index 
species of the underlying zone which represents the lowest Paleocene or the Danian, 
and that G. angulata angulata was never recorded from the type Danian, justifies the 
position of the G. angulata Zone at the Middle of the Paleocene series. From an 
evolutionary point of view, this zone with truncated Globorotalia is regarded as a 
transitional stage between the underlying rounded Globorotalia Zone and the over- 
lying zone with sharply-keeled Globorotalia. This is also substantiated by the fact 
that this intermediate zone is represented by a relatively smaller thickness of strata. 
However, as its characteristic assemblage of planktonic Foraminifera can not be 
assigned to either the overlying or the underlying zones, it is advisable to treat 
it separately. The lower boundary of this zone is marked by the first appearance 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 31 

of its index species, and its upper boundary is marked by the first appearance of the 
sharply keeled Globorotalia assemblage, typified by G. velascoensis velascoensis 
(Cushman) and G. pseudomenardii Bolli. 

3. An upper zone characterized by an assemblage of rugose Globigerina and 
sharply-keeled and/or rugose Globorotalia species. In this zone, the tendency 
towards the development of a marginal keel and/or a rugose surface which started 
with the early representatives of Globorotalia in the Lower Paleocene, is fully 
achieved. At the bottom of this zone the first known sharply-keeled Globorotalia, 
represented by G. velascoensis velascoensis (Cushman) and G. pseudomenardii Bolli, 
make their appearance. G. pseudomenardii dies out towards the middle but G. 
velascoensis velascoensis continues to the top, where it dies out completely. Globoro- 
talia velascoensis with its three subspecies, G. velascoensis velascoensis, G. velascoensis 
parva, and G. velascoensis caucasica, represent the dominant forms of the zone which 
is thus known as the G. velascoensis Zone. This zone is considered to represent the 
Upper Paleocene in Mexico, in the Gulf and Atlantic Coastal Plains of the U.S.A., 
in the Caribbian region, in Southern France, in Italy, in North Africa, in the Middle 
East, in Pakistan-India-Burma region, in New Zealand and in the U.S.S.R., although 
the characteristic species are not recorded in the type Upper Paleocene of Western 
Europe (the Landenian) which is mainly of continental and lagoonal facies. However, 
as previously mentioned, the sharply keeled Globorotalia assemblage of the G. 
velascoensis Zone represents the maximum development of a continuous evolutionary 
trend which started at the base of the Paleocene, typified by the bio-series : Globoro- 
talia pseudobulloides^G. trinidadensis^G. uncinata uncinata^G. angulata angulata^- 
G. angulata abundocamerata^-G. velascoensis velascoensis (Text fig. 15). This 
continuous evolutionary sequence is paralleled by similar lineages throughout the 
Paleocene, and proves that there are three distinct stages in the development of the 
genus Globorotalia : the rounded stage, the truncated stage and the sharply keeled 
stage. It also justifies consideration of these three stages as divisions within one 
natural unit, hence the position of the G. velascoensis Zone as the Upper Paleocene and 
the underlying two zones as the Middle and Lower Paleocene respectively. Analysis 
of previously recorded planktonic Foraminifera in the Paleocene of different parts 
of the world, shows the existence of these three stages, and thus substantiates the 
division of the Paleocene proposed here. 

The Paleocene-Lower Eocene Boundary 

The fact that the Upper Paleocene in its type region is represented by non-marine 
sediments, and that the planktonic Foraminifera in the type Lower Eocene are 
hardly known, made it difficult to decide the position of the Paleocene-Lower 
Eocene boundary with certainty. However, as previously suggested by Bolli 
(1957a, 19596), Loeblich & Tappan (1957a, 6) and Bolli & Cita (1960a, 6), and as 
reasoned above, this boundary is drawn at the top of the Globorotalia velascoensis 
Zone, although Olsson (i960) included the latter zone within the Lower Eocene. 
Analysis of the planktonic foraminiferal content of the G. velascoensis Zone shows 
clearly that it has more species in common with the underlying Paleocene zones than 



32 1'1'PER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

with the overlying G. wilcoxensis Zone which is here taken to mark the base of the 
Eocene. Moreover, as mentioned above, the planktonic Foraminifera of the G. 
velascoensis zone constitute, with those of the underlying Paleocene zones, a contin- 
uous evolutionary series which unites them as one natural unit. On the other hand, 
the disappearance of several typical Paleocene forms at the base of the G. wilcoxensis 
Zone and the appearance of new forms and new evolutionary tendencies, clearly 
distinguishes this zone from the underlying Paleocene. In the G. wilcoxensis 
Zone, a tendency towards reduction in the size of test and increase in the surface 
rugosity and/or the degree of development of the marginal keel in the genus Globoro- 
talia, is clearly documented. As a result the majority of the planktonic Fora- 
minifera in this basal Eocene zone have a highly rugose surface and/or a very well 
developed marginal keel. In this connection, it is worth noting that the rare 
planktonic forms recorded by Kaasschieter (1961) from the type Ypresian of Belgium, 
although misidentified, are highly rugose, as are all the forms recorded by Berggren 
(1960a) from the Ypresian of Denmark and northwestern Germany. Moreover, the 
planktonic Foraminifera of the G. wilcoxensis Zone clearly correlate it with the basal 
Eocene of Mexico, the Gulf and Atlantic Coastal Plains of the U.S.A., the Carib- 
bean region, Denmark, northwestern Germany, southern France, Italy, North Africa, 
the Middle East, Pakistan-India-Burma region, New Zealand and the U.S.S.R., 
where similar planktonic foraminiferal assemblages have been recorded. This is 
substantiated by the fact that in the sections studied, a flood of Nummulites, Oper- 
culina, Assilina and Discocyclina, amongst numerous typical Eocene forms, is 
clearly observed in the G. wilcoxensis Zone, while the genus Nummulites, represented 
by rare specimens of the very primitive form N. deserti de La Harpe, is alone recorded 
in the uppermost part of the underlying zone. However, a detailed study of the 
planktonic Foraminifera in the type Lower Eocene is needed before a definite 
decision on the position of the Palecoene/Lower Eocene boundary can be reached. 

B. The Upper Cretaceous-Lower Tertiary in Egypt 

The classification of the Upper Cretaceous-Lower Tertiary rocks of Egypt was 
first attempted by Zittel (1883), who considered the fossiliferous marine succession 
overlying the Nubia sandstone of the Western Desert Oases to belong collectively to 
the Danian, which he regarded as the youngest stage of the Cretaceous system. As 
a result, he assigned the underlying unfossiliferous Nubia sandstone to the Upper 
Senonian, while he considered the nummulitic limestone beds which cap the succes- 
sion to be of Lower Libyan (Lower Eocene) age. However, he overlooked the 
succession of shales between the top of his Danian and the base of the nummulitic 
limestone, which were later recorded by various authors in the Oases and in other 
parts of Egypt, and were considered by Beadnell (1905) as passage beds between the 
Cretaceous and the Tertiary systems. Moreover, Zittel advocated the absolute 
conformity of the Cretaceous-Tertiary succession in southern Egypt, a concept 
which, as discussed below, was uncritically followed by most stratigraphers and led 
to great confusion. 

Zittel classified the strata he considered to be Danian in the Western Desert Oases 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 33 

into three distinct rock units which he described from the base upwards as follows : 

1. Beds of Exogyra overwegi von Buch, (Overwegischichten). 

2. Greenish and ashen-grey paper-like shales. 

3. Snow-white, well-bedded limestones or earthy chalk with Ananchytes ovata. 

The fossils collected by Zittel from these three rock units were described by Quass 
(1902) and Wanner (1902) who confirmed Zittel's classification, assigning all these 
rock units to the Danian. Moreover, Quass considered Zittel's shale and chalk units 
as two different fades of the same stratigraphical horizon, which he regarded as the 
Upper Danian. 

Apparently Zittel used the term Danain in a much broader sense than that of the 
original definition of the term. While no known ammonifies or inocerami are 
recorded to range up into the type Danian, Zittel recorded the genera Libycoceras, 
Baculites and Inoceramus in his " overwegischichten ", but still included it in the 
Danian. Probably he was confused by Mayer-Eymar (1872) who had extended the 
Danian to include the Campanian, the Maestrichtian, and the Danian proper and 
thus added to the confusion regarding the limits between these stages and sub-stages. 
However, analysis of Zittel's Danian in the light of the present investigation shows 
that it includes the Upper Campanian, the Maestrichtian and most of the Paloecene. 
It also indicates a marked break between the Maestrichtian and the overlying 
Paleocene strata in spite of Zittel's emphasis on the absolute conformity of the succes- 
sion. Nevertheless, Zittel's concept and classification of the Danian in Egypt were 
generally followed by later authors, e.g. Ball (1900), Beadnell (1901, I905),0ppenheim 
(1902) and Hume (1911), where the latter included as Danian all the succession of 
strata between the top of the Campanian and the base of the Lower Eocene. 

Blanckenhorn (1900) considered Zittel's " overwegischichten " to belong to the 
Maestrichtian, which he equated with the Dordonian, Upper Aturian and Lower 
Danian. Later in 1921, he reconsidered the " overwegschichten " to belong to the 
Campanian and related the other two divisions to the Danian (which he regarded as 
the youngest stage of the Senonian), ignoring completely the Maestrichtian. 
Apparently he followed de Grossouvre (1897, 1901) who had included the Maestrich- 
tian within the Campanian as its uppermost part. However, Fourtau (1904), 
following Arnaud (1897), considered the Upper Senonian to include the Campanian 
as its lower horizon and the Maestrichtian as its upper, while he regarded the Danian 
as a distinct stage, younger than and equal in rank to the Senonian stage. He also 
considered some fossils of Zittel's " overwegischichten " to belong to the Campanian 
and reasonably stated that the limit between the Maestrichtian and the Danian in 
Egypt should be drawn at the top of the highest bed with ammonites. 

Beadnell (1905) classified the Upper Cretaceous-Lower Tertiary rocks of the Nile 
Valley, south of Esna, into Campanian, Danian, Passage beds and Lower Libyan, 
advocating the absolute conformity of the succesion which was previously emphasized 
by Zittel (1883). Following the general belief of his time, he ignored the Maestricht- 



34 ll'l'ER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

ian, probably including it within the Campanian, and considered the Danian as the 
youngest stage of the Cretaceous system, but he did not state to which system his 
" Passage beds " belong. Thus he assigned the oyster limestone and the associated 
bone beds, which directly overlie the Nubia sandstone, to the Campanian, and the 
overlying succession of shales, marls and chalks to the Danian which he correlated 
with Zittel's Danian of the Western Desert Oases. He regarded the shales between 
the top of the Danian and the base of the nummulitic limestones above, (Beadnell's 
Esna shales) , as passage beds between the Cretaceous and the Teritary and referred 
the overlying nummilitic limestones to the Lower Libyan (Lower Eocene) (see 
Text-fig. 4). 

Hume (191 1) classified the same succession as Campanian, Danian and Lower 
Eocene, including Beadnell's Passage beds within his Danian. He correlated this 
succession with others in the Western Desert Oases, in Wadi Quena and in northern 
Sinai. He also used these widely-spaced sections to demonstrate the gradual advance 
of the Upper Cretaceous sea over the Egyptian territory, invading it from the north- 
east, depositing limestones in the northern part, sandstones in the south, and shales, 
marls and chalks in between. The relative distribution of these facies both in 
space and time clearly marks the gradual invasion of the sea, and was used by 
Hume as a means for classifying the Upper Cretaceous rocks of Egypt into five main 
types from the north southwards. He suggested that folding towards the end of 
Cretaceous times led to the formation of a series of parallel ridges rising from the 
bottom of the Upper Cretaceous sea as islands or submarine ridges. Along these, 
erosion took place, while deposition continued in the troughs in between ; hence 
the existence of unconformities and disconformities between the Cretaceous and the 
Tertiary systems along these ridges, and continuous depositon in the basins separa- 
ting them. However, the controversy about the nature of the Cretaceous-Tertiary 
boundary continued, and the vast concept of Zittel's Danian was followed until the 
use of Foraminifera modified the old beliefs and introduced new and revolutionary 
concepts. 

On the basis of small Foraminifera, Henson (1938) established two zones in the 
Upper Cretaceous-Lower Tertiary succession of Palestine and adjoining countries 
(including Egypt), a lower " Globotruncana-Guembelina Zone " of Upper Cretaceous 
age, and an upper " Globigerina-Globorotalia Zone, of transitional character between 
the Cretaceous and the Tertiary. He regarded this transitional zone as extending 
from the highest Danian into the early Eocene, and considered the junction between 
these two zones as " a reasonable approximation of the Cretaceous-Eocene contact ". 
In other words, he considered the Globotruncana-Guembelina Zone to represent the 
Danian (although the genus Globotruncana does not occur in the Danian) and the 
Globigerina-Globorotalia Zone to represent the early Eocene, apparently including the 
Paleocene. Moreover, he noticed that, even when there is no evidence of a break in 
sedimentation between the Cretaceous and Eocene systems, the fauna of the trans- 
itional zone is not equally developed in the various sections examined, and thus he 
concluded that an imperceptible gap between the Cretaceous and Eocene systems 
must exist. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 35 

On the other hand, Faris (1947) described the Upper Cretaceous-Lower Tertiary 
succession in the Taramsa-Tukh area, near Quena, in Upper Egypt, and echoed 
Zittel (1883) in advocating the absolute conformity of the Cretaceous-Eocene 
succession everywhere in Upper Egypt. He divided the Taramsa-Tukh section into 
a lower, Cretaceous part and an upper, Eocene part, and divided the former into 
Maestrichtian and Danian, but, failing to define the boundary between them, he 
included both on his chart as Danian. He also considered his Eocene to include the 
so-called " Montian ? " at its base and Londinian at its top ; but, while in the text he 
considered his basal white limestone bed with G. cf. velascoensis as the top of his 
Danian he included it on the chart at the base of the Eocene. However, analysis of 
the succession as described by him shows that his Danian includes the Middle and 
part of the Upper Maestrichtian, as well as most of the Paleocene. His " Montian ? " 
includes the uppermost Paleocene and the basal Eocene, while his Londinian repre- 
sents the rest of the Lower Eocene. Moreover, a stratigraphical break between the 
Maestrichtian and the Paleocene in his section is clearly evident (cf. the present 
study), in spite of his repeated emphasis on the absolute conformity of the succession. 

Tromp (1949, 1952), using his quantitative generic method in foraminiferal analysis, 
noticed a number of micro-faunal differences between the uppermost Cretaceous and 
the basal Eocene in Egypt, Turkey, and the Middle East in general. Nevertheless, 
he considered the nature of the contact between these two systems to be gradational 
and denied the existence of any indications of an erosional hiatus at the Cretaceous- 
Eocene boundary in the Middle East. However, in agreement with Henson (1938), 
he placed this boundary at the junction of the Globotruncana-Guembelina Zone with 
the overlying Globigerina-Globorotalia Zone, although he considered the top of the 
former zone to represent the top of the Maestrichian, not the Danian as previously 
suggested by Henson (1938). Moreover, he stated (1949) that the Cretaceous- 
Eocene boundary in the Middle East cuts through the so-called Danian and makes 
the term superfluous. As a result, he suggested that the term should be eliminated 
at least in the Middle East, and added that " Further evidence suggests that in other 
countries also the term Danian is useless as an accurate stratigraphic unit and should 
be abandoned ". He also mentioned that by using the quantitative generic method 
in forminiferal analysis, he had been able to classify the Senonian of Egypt and of 
Turkey into three stratigraphical units only, which he tentatively termed the 
Santonian, Campanian and Maestrichtian. 

Nakkady (1949, 1950, 1951a, 1952, 1955) studied the Foraminifera of six Upper 
Cretaceous-Lower Tertiary sections from widely separated areas in Egypt. 
He concluded that the use of rock units as time-rock units (suggested by Zittel 1883 
and adopted by later authors) was very misleading, and thus suggested dropping the 
rock units and using bio-zones instead. Nakkady established three zones in the 
Cretaceous-Tertiary transition period of Egypt, a lower Globotruncana Zone of 
Maestrichtian age, an upper Globorotalia Zone of Paleocene age, and an intervening 
Buffer zone, described as distinguished by the complete absence or extreme scarcity 
of both Globorotalia and Globotruncana, which he assigned to the Danian. In 



36 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

correlating these six widely spaced sections, Nakkady (1951a, chart) showed the 
existence of great differences in the thickness and the stratigraphical position of his 
Buffer zone, and in the position of the upper limit of his Maestrichtian Globotruncana 
Zone in the different sections studied. However, no attempt was made to explain 
this marked variation, and instead of interpreting it in the obvious way, as a marked 
stratigraphical break, Nakkady emphasized the conformity of the succession and 
stated (1951a) that " The chalk and the overlying Esna shales are two phases of 
continuous sedimentation representing the last sequence of deposition at the close 
of the Mesozoic and the advent of the Tertiary ". Moreover, he described the Esna 
shale fauna as transitional in character, and thus followed Beadnell (1905) in regard- 
ing the Esna shales as passage beds between the Cretaceous and the Eocene. Further- 
more, despite the discovery of breaks between the Cretaceous and the Tertiary in 
successions previously described as conformable throughout (e.g. Le Roy 1953), 
Nakkady did not reconsider his statements. On the contrary, this author (1957, 
1959) on one side, and Said & Kenawy (1956) and Said (i960) on the other, started a 
lengthy argument on the so-called retardation in the appearance of Globorotalia 
species in the various sections studied, and its different implications, but overlooked 
the fact that this can be explained by the occurrence of breaks of varying magnitude 
between the Cretaceous and the overlying Tertiary rocks. 

Le Roy (1953) described the Upper Cretaceous-Lower Tertiary succession of the 
Maqfi section, on the northeastern corner of the Farafra Oasis, Western Desert, 
Egypt, and analysed its small foraminiferal fauna. He did not discuss the Nubia 
variegated claystones and sandstones which constitute the basal part of the succes- 
sion, but stated that they may probably be of pre-Maestrichtian age and may be 
separated from the overlying chalk by an unconformity, interpreted by the abrupt 
change in lithology between the two formations. Nevertheless, he recognized in the 
overlying succession two major divisions demarcated by a minor lithological change 
and a major palaeontological hiatus, a lower chalk unit of Upper Cretaceous (Mae- 
strichtian) age, which he termed " Unit A " and an overlying succession of four rock 
units (IV, III, II and I) of Lower Tertiary age. He recorded the abrupt faunal 
change between " Unit A " and " Unit IV " which he interpreted as a probable 
disconformity and stated that it could logically indicate the Mesozoic-Cainozoic 
boundary. 

Le Roy stressed the difficulty in assigning the Tertiary part of the succession to the 
Paleocene or the Lower Eocene, and stated that " Until the Egyptian Paleocene is 
more specifically correlated in terms of the European section, the writer favours 
allocating Unit IV to the basal Eocene ". However, comparison with the present 
study proves this " Unit IV " to be of Upper Paleocene age, and substantiates a 
marked break between the Maestrichtian and the overlying Upper Paleocene. On 
the other hand, Le Roy recorded a distinct erosional surface between his " Unit IV ' 
and the overlying " Unit III ", and a probable disconformity between the latter and 
" Unit II ". This drove Nakkady (1957) to interpret " Unit III " as a slipped 
mass of the nummulitic limestone capping the succession. However, Le Roy 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 37 

considered Units III and II as Lower Eocene, and added that although the age of 
" Unit I " is open to question, he tentatively assigns it to the Lower Eocene as well. 

The same section was discussed by Nakkady (1957) .where he interpreted Le Roy's 
Lower Tertiary units as representing the Danian, Montian, Thanetian and Ypresian, 
advocating the conformity of the succession. On the other hand, Said & Kerdany 
(1961) described the same succession, confirming Le Roy's previous statement of a 
major palaeontologic hiatus between the Creataceous and the Tertiary, and assigning 
Le Roy's Units IV, III and II to the Landenian and his Unit I to the Ypresian. 
However, analysis of their recorded planktonic Foraminifera shows that their 
Landenian includes both the uppermost Paleocene and the Lower Eocene. Globoro- 
talia velascoensis which characterizes the Upper Paleocene and marks the Paleocene- 
Lower Eocene boundary by the disappearance of its last survivors, was recorded by 
Le Roy (1953) as characteristic of his Unit IV only, and its range was slightly 
extended by Said & Kerdany (1961) to the basal part of Le Roy's Unit II. Never- 
theless, they included the whole of Unit II which was stated by them to have a 
thickness of between 120 and 160 metres, together with the underlying Units III and 
IV within the Landenian. Correlation with the Esna-Idfu sequence, shows clearly 
that the part of this succession between the upper limit of G. velascoensis and the 
base of the hard crystalline limestone (Le Roy's Unit I) can be equated with the 
' Thebes calcareous shale member " of the Esna-Idfu region, which is here considered 
to be of Lower Eocene age. 

Nakkady & Osman (1954) discussed the genus Globotruncana in Egypt and its 
value in stratigraphical correlation, using Nakkady's previous sections and two other 
sections in western Sinai, the Qabeliat and the Sudr sections. Nevertheless, in 
correlating the Campanian-Maestrichtian succession of these two relatively close 
sections, the authors could not establish the same zones. Moreover, the record by 
Nakkady & Osman of forms such as Globigerina pseudotriloba, G. quadrata, G. 
cretacea var. esnehensis in Cretaceous strata is definitely erroneous, as these forms are 
only known from the Tertiary. Similarly, their records of Globotruncana contusa, 
G. caliciformis, G. aegyptiaca var. duwi and G. esnehensis in the Campanian, and forms 
such as Globigerina cretacea d'Orbigny [=Globotruncana cretacea (d'Orbigny)] and its 
synonym G. globigerinoides Brotzen, and Globigerinella aspera, in the Maestrichtian, 
are very much doubted. The former species are restricted to the Maestrichtian, 
while the latter are not known from this stage. 

Youssef & Shinnawi (1954) described the succession in Wadi Sudr area, Western 
Sinai, Egypt, where they showed the difficulty in sub-dividing the Senonian, the 
Danian and the overlying Paleocene. Between the top of their Lower Senonian and 
the base of their Lower Eocene, they described a succession (246-5 metres thick) of 
limestones, chalky limestones and chalk with a thin shaly intercalation at its base 
They regarded this succession as Campanian-Maestrichtian-Danian and partly 
Paleocene, advocating the conformable relationship between the Cretaceous and the 
Tertiary systems. They recorded some planktonic Foraminifera in their shaly bed 
which they tentatively considered at the base of the Maestrichtian. Of particular 



3S UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

interest are Globotruncana area (Cushman) and G. area var. esnehensis Nakkady 
( =G. esnehensis) and G. aegyptiaca Nakkady, an assemblage which indicates a 
Maestrichtian age (probably Middle to Upper Maestrichtian). However, their 
records of Globigerina cretacea d'Orbigny, G. linaperta Finlay and G. quadrata White 
are erroneous ; the first, (which is a true Globotruncana, not a Globigerina) does not 
extend above the Upper Campanian, the second is known from the Lower Eocene and 
the third is definitely Paleocene. These forms were probably confused with apparently 
similar Rugoglobigerina and Hedbergella species, but nothing can be added until the 
planktonic Foraminifera of the succession are examined in detail. 

Youssef (1954) described the succession in the Gebel Owaina section, as summarized 
above, attributing it to the Maestrichtian, Danian, Paleocene and Lower Eocene, 
and advocating the conformity of the succession. However, the present study 
(see Text-fig. 4) shows that his Danian includes most of the Paleocene, and that his 
Paleocene includes both the uppermost part of this series and the basal Eocene. 
Moreover, it indicates a marked break between the Maestrichtian and the overlying 
Paleocene, in spite of Youssef's statement that the succession is apparently conform- 
able throughout. 

Said & Kenawy (1956) described the Foraminifera of the Upper Cretaceous-Lower 
Tertiary succession of the Nekhl and the Giddi Sections, in northern Siani, Egypt. 
Following Nakkady (1951a), they recognized in the two sections a lower unit of Maes- 
trichtian age, characterized by the abundance of Globotruncana and Guembelina 
species, a middle unit, of Danian age, characterized by the absence of Globotruncana 
and by the presence of a flood of Globigerina together with certain other benthonic 
forms, and an upper unit of Paleocene age, characterized, according to them, by the 
appearance of various species of Truncorotalia and Globorotalia together with several 
distinctive benthonic forms. They noted that the limits of these biozones are 
independent of the lithological boundaries, a fact previously recognized by Nakkady 
(1951a). They also followed Hume (1911) and Shukri (1954) in attributing the 
varied nature of the Cretaceous-Tertiary boundary in geologically adjacent areas in 
northern Egypt, to deposition over anticlines and synclines which had previously 
emerged from the bottom of the Upper Cretaceous sea. These folds were attributed 
to the Syrian arc movement which began at least as early as the Turonian, and which 
was intermittently active until late Oligocene time. While erosion took place on the 
anticlines, deposition continued in the adjacent troughs. With this idea in mind, 
they tried to analyse the stratigraphical succession in the two sections, believing that 
one of them, the Nekhl section, lay in the heart of a trough in the late Cretaceous sea, 
while the other, the Giddi section, lay on the flank of one of the main structural highs 
of that time. However, when the accepted index fossils for this period, the plank- 
tonic Foraminifera, showed the incorrectness of this imaginary position of the two 
sections, they tried to deprive these forms of their value in stratigraphical zonation 
and world-wide correlation stating that " . . . . in Egypt, where the bottom topography 
of the Upper Cretaceous-Lower Tertiary sea was affected by great lateral folding 
movements, environmental conditions may differ from one place to another rather 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 39 

rapidly, and this makes the use of planktonic species of rather limited value. The 
only exceptions to this rule seems to be the Globotruncana and Giimbelina species, 
which are assumed by many authors to have been planktonic " and added " .... we 
have abandoned the classic and oft-repeated zoning based on the planktonic foramini- 
fera Globigerina and Truncorotalia. We feel that these forms are facies fossils, 
which, may have some zoning value but which occur, like their descendants in modern 
times, only in open and moderately deep seas ". Thus, while at the beginning of their 
work they followed Nakkady 's zonation of the Upper Cretaceous-Lower Tertiary rocks 
of Egypt into a Globotruncana-Guembelina Zone of Maestrichtian age, a Globigerina 
or Buffer Zone of Danian age, and a Globorotalia Zone of Paleocene age, they used 
Bolivinoides and Neoflabellina for the classification of the succession, and thus confused 
the correlation between the two sections. Without discussing the disadvantages 
and mistakes of such a classification (e.g. their record of Neoflabellina rugosa, a 
known Campanian form, in their Upper Maestrichtian, Danian and Paleocene), 
these authors stated that " These species are, unfortunately, rare in the Egyptian 
material and may escape notice ". However, other than the undisputed value of 
Globorotalia in Lower Tertiary stratigraphy and correlation, the fallacy of the whole 
picture presented by Said & Kenawy (1956) is clearly demonstrated by their text- 
fig. 4. In this text-figure, the parallelism between their Globotruncana time surface 
and their Truncorotalia surface, indicates that the folding movement which shaped 
the strata of the two sections in their present day form, definitely took place after 
the appearance of the sharply-keeled globorotalias, i.e. at least after the beginning 
of the Upper Paleocene and not before the deposition of the Maestrichtian as suggest- 
ed by these authors. Indeed, a similar folding movement which affected the Upper 
Cretaceous-Lower Tertiary rocks of the Esna-Idfu region is of post-Lower Eocene 
age. Nevertheless, this does not deny the possibility that the Upper Cretaceous 
sea bottom was affected in certain regions by intermittent folding movements 
(which might even have started long before the Upper Cretaceous), as suggested by 
Hume (1911) and Shukri (1954), and substantiated by deep drilling in the northern 
part of the Western Desert (see Said 1962). One of the most striking contradictions 
in Said & Kenawy's discussion is their statement that " The Maestrichtian-Danian 
boundary is therefore of importance in determining the structural position of the 
locality from which a section was taken. When this boundary coincides with the 
lithologic boundary between the chalk and the Esna shale, it indicates a structural 
low, whereas its occurrence within the Esna shale indicates a structural high in the 
late Cretaceous sea. This idea is further strengthened by the fact that we find the 
thinnest Danian, followed immediately by the Truncorotalia zone, in the structurally 
low areas ". Contrary to this conclusion, the present study has shown that the 
variation in the thickness of the Danian strata, which are generally of the same 
lithological composition, is mainly due to the occurrence of stratigraphical breaks of 
varying magnitude between the Maestrichtian and the overlying Paleocene, and that 
the thinnest Danian occurs in areas which were subjected to more uplift and/or more 
erosion, not in the structually low areas, as suggested by these authors. On the 
other hand, correlation with the succession in the Esna-Idfu region shows clearly 



4 o UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

that their Lower Eocene of the Giddi section is partly of Upper Paleocene age, that 
their Upper Paleocene of the Nekhl section is definitely Lower Eocene, and that the 
presence of the Danian in the two sections is to be doubted because of the absence of 
typical Danian forms such as Globorotalia compressa (Plummer), G. pseudobulloides 
(Plummer) G. trinidadensis Bolli and Globigerina daubjergensis Bronnimann. More- 
over, it points to the occurrence of a stratigraphical break between the Maestrichtian 
and the overlying paleocene, substantiated by the reduced thickness of the shale 
succession between the top of the Maestrichtian and the first appearance of G. 
velascoensis, especially in the Nekhl section (although their G. velascoensis is mis- 
identified) . 

Hassan (1956) studied the type area of Zittel's " overwegischichten " in the 
Kharga Oasis, which he considered to be of Maestrichtian age, and divided it into 
the following three faunal zones : 

1. A lower zone (A) with Isocardia chargensis, Bostrychoceras polyplocum, 

Nostoceras sp., Nautilus desertorum, Baculites anceps, Chlamys mayereymari 
and Trignoarca cf. gauldrina. 

2. A middle zone (B) with Exogyra overwegi, Plicatula instabilis, Plicatula 

aschersoni, Veniella (Roudaireia) drui, Cardita libyca and Hoplitopiacenti- 
ceras awadi. 

3. An upper zone (C) with Cardita libyca and no ammonites. 

He followed Laffitte (1934, 1939) in considering the lower limit of the Maestrichtian 
in North Africa to be marked by the appearance of Orbitoides tissoti, Bostrychoceras 
polyplocum and Libycoceras ismaeli and thus considered his zone (A) to be of Lower 
Maestrichtian age. However, as mentioned by Leriche (1927, 1929), Abrard (1931, 
1948) and Jeletzky (1951), Bostrychoceras polyplocum characterizes the Upper 
Campanian in its type area, and Hassan's zone (A) should therefore belong to the 
Upper Campanian and not the Lower Maestrichtian, if his record of Bostrychoceras 
polyplocum is correct. 

In his zone (C), Hassan stated that " Not a single ammonite has been found in the 
third zone which is crowded with Cardita libyca ". Nevertheless, he assigned this 
zone to the Upper Maestrichtian, although in the same paper he mentioned that 
Fourtau (1904) had clearly reasoned that the limit between the Maestrichtian and 
the Danian should be drawn at the top of the highest bed with ammonites in the 
Libyan Desert. 

Nakkady (1959) described the same section and assigned the lower part of the 
succession to the Maestrichtian, the Cardita beds and the overlying shale and chalk 
section to the Danian and the nummulitic limestone above, to the Montian. However, 
analysis of his recorded planktonic Foraminifera shows that his Danian actually 
represents the whole Paleocene, while his Montian represents the Lower Eocene. 
Moreover, a comparison of the succession, as described by both Hassan (1956) and 
Nakkady (1959), with the sections studied, clearly points to the occurrence of a 
marked stratigraphical break, in spite of the fact that these authors described the 
succession as perfectly conformable. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 41 

Nakkady (1957) reviewed the biostratigraphy of the Upper Senonian and the 
Paleocene of Egypt, which he tried to correlate with corresponding units in other 
parts of the world. He considered the Senonian to include the Coniacian and the 
Santonian as its lower part, and the Campanian and the Maestrichtian as its upper, 
and divided the Paleocene into a lower part including the Danian and the Montian, 
and an upper including the Thanetian and Sparnacian. However, although he 
only discussed what he described as Campanian, Maestrichtian, Danian and Montian, 
analysis of his faunal lists shows that his Montian actually represents the Lower 
Eocene and his Danian, the whole Paleocene. Moreover, comparison of the eight 
sections correlated by him (Text-fig. 2) with the succession in the Esna-Idfu region, 
indicates a marked break between the Upper Cretaceous and the overlying Tertiary 
rocks in each of the described sections, despite the fact that he strongly advocated 
the conformity of the whole succession. 

Youssef (1957) described the Upper Cretaceous-Lower Tertiary succession in the 
Kosseir area, recognizing the following four formations from the base upwards : 
the Nubia sandstone, the Kosseir variegated shales, the Duwi formation and the 
Esna shales. He included the first three formations within the Campanian (although 
he considered the top part of the last formation to be of basal Maestrichtian age), and 
regarded the Esna shales as representing most of the Maestrichtian, the Danian (or 
Dano-Montian) and the Paleocene. He did not discuss the stratigraphical position 
of the overlying limestone beds, but included them on his columnar section within 
the Paleocene, and considered the succession to be conformable throughout. He 
mentioned the difficulty in establishing the lower and upper limits of the Maestrich- 
tian, but following Laffitte (1939) he considered the base of this stage to be marked 
by the appearance of Libycoceras ismaeli Zittel and its associated fauna, which is here 
considered to be of Upper Campanian age. The succession compares well with that 
of the Esna-Idfu region, although the phosphate formation is much more developed 
in the Kossier area. Correlation of the two sections shows that the base of Youssef's 
Maestrichtian should be included in the Upper Campanian, and the Maestrichtian- 
Danian boundary should cut somewhere through the 105 metres thick shale bed 
considered by him to lie at the base of the Danian. This shale bed actually includes 
the top of the Maestrichtian and most of the Paleocene. Moreover, it is felt, by 
comparison with the succession in the Esna-Idfu region, that a careful examination 
of the above-mentioned shale bed may prove the existence of a stratigraphical 
break marking the Mesozoic-Cainozoic boundary, despite Youssef's emphasis on the 
conformity of the succession. 

Faris & Hassan (1959) described the Upper Cretaceous-Lower Tertiary succession 
of the Um-El-Huetat section, Safaga area, Red Sea coast, which they divided into 
seven successive units. They considered the lowest two units (I and II) as Lower 
Senonian and even older, Unit III as Santonian to Campanian, Units IV and V as 
Lower and Upper Maestrichtian respectively, Unit VI as Danian to Paleocene and 
Unit VII as Lower Libyan. However, analysis of the succession as summarized by 
them shows that the upper part of their Unit VI which they collectively described as 
" Danian to Paleocene ", is of Lower Eocene age. The " Eponides lotus fauna " 



ji UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

which was described by Le Roy from the Maqfi section and with which they correlated 
this part of their succession, is of Lower Eocene age (see p. 37). Again, their 
description of the underlying zone as characterized by Aturia cf. praeziczac is very 
misleading, as the latter species characterizes, in the Luxor section, an horizon 
equivalent to the " Eponides lotas fauna " of the Maqfi section. Moreover, in spite 
of a marked break in the succession, and the absence of the Lower and Middle 
Paleocene in the Maqfi section, Eponides lotus was found to appear at a vertical 
distance of about 120 metres from the underlying Maestrichtian surface, while they 
recorded this species in a lithologically identical succession, at a vertical distance of 
only 70m. from the top of their Maestrichtian, and advocated the conformity of the 
succession throughout. However, until the succession is more carefully examined, 
nothing much can be added, although the Foraminifera of two samples from the 
Maestrichtian part of the succession (described by Ansary & Fakhr 1958), included 
some rare planktonic forms. Nevertheless, a probable stratigraphical break between 
the Maestrichtian and the overlying Paleocene is indicated by the marked reduction 
in the thickness of the strata assigned to the latter series. 

Said (i960) recorded fourteen species of planktonic Foraminifera from what he 
described as Esna shale and the overlying Thebes formation of the Gebel Gurnah 
section, at Thebes (on the western bank of the Nile, facing Luxor). He concluded 
that the " Esna shale " is Landenian in age while the Thebes limestone is Ypresian. 
Analysis of his described planktonic Foraminifera, and comparison with the present 
study shows that both the shales and the limestones are of Lower Eocene age. It 
also indicates that the shaly part of the succession is equivalent to the " Thebes 
calcareous shale member " of the Gebel Owaina section, which is here equated with 
the Globorotalia wilcoxensis Zone of earliest Eocene age. This throws doubt on the 
validity of the identification of forms recorded by Said, e.g. G. velascoensis (Cushman), 
G. imitata (Subbotina), G. conicotruncata (Subbotina) and Globigerina trilocidinoides 
Plummer, which are restricted to the Paleocene. However, the possibility that the 
basal 1-5 metres of the succession may be of uppermost Paleocene age is not 
excluded. Indeed comparison of his figures and descriptions with the original 
descriptions and figures of the above-mentioned species, and with the specimens 
described in the present study shows that his forms need to be renamed and re- 
described in more detail. 

Hermina, Ghobrial & Issawi (1961) described the Upper Cretaceous-Lower 
Tertiary succession of the Dakhla Oasis, Western Desert, Egypt, and in disagreement 
with Zittel (1883) and Beadnell (1901), they recorded a marked break between the 
Maestrichtian and the overlying Danian in most of their measured sections. How- 
ever, they noticed that the gap represented by this break is gradually minimized 
westwards where they stated that "... a monotonous shale section follows above 
the uppermost zone of the Upper Maestrichtian with possible conformable relation- 
ship ". 

These authors considered the unfossiliferous Nubia formation to be of uppermost 
Campanian or Lower Maestrichtian age (being conformably overlain by rocks they 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 43 

regarded as of Lower Maestrichtian age), and classified the overlying strata as 
Maestrichtian, Danian, Paleocene and Lower Eocene. Moreover, they divided both 
their Maestrichtian and Danian into lower, middle and upper units, and their 
Paleocene into Lower and Upper Paleocene. However, it is evident from their 
description that their divisions were very tentative and hardly based on any correl- 
ation with the type or corresponding sections in other parts of the world. Neverthe- 
less, comparison with the succession in the Esna-Idfu region showed that : 

1. Their Lower Maestrichtian should be assigned to the Upper Campanian, as 

both the Bostrychoceras polyplocum and the Inoceramus regularis faunal 
assemblages with which they tried to equate their Lower Maestrichtian, 
are of Upper Campanian age (sse " General Discussion " above). 

2. Their Middle and Upper Maestrichtian, probably represent the most complete 

Maestrichtian section as yet known in southern Egypt. The upper zone 
of their Upper Maestrichtian which they distinguished by the presence of 
Trigonoarca gauldrina and Cardita dakhlensis, is missing in the Esna-Idfu 
region and was reported by them to be missing from most of their measured 
sections. 

3. In spite of the above-mentioned fact, their statement of a possible conformable 

relationship between the Cretaceous and the Tertiary systems in the western 
part of the Oasis, still needs further support. Their only argument is the 
existence of a zone with Globigerina spp. and no Globorotalia of the compressa 
group on top of the Maestrichtian Globotrnncana zone. Yet, the same zone is 
recorded at the base of the type Danian, where a physical break in the 
succession and a major faunal break are documented. 

4. Both their Danian and Paleocene are extremely difficult to correlate, although 

their Ostrea hypoptera Zone which they regarded as Upper Danian, corresponds 
in the present study to most of the G. velascoensis Zone which represents 
the Upper Paleocene. If this is the case, their Danian should be regarded 
as representing most of the Paleocene, and the Paleocene-Lower Eocene 
boundary should cut through their Upper Paleocene. However, a 
detailed study of the planktonic Foraminifera of this succession is needed to 
establish a proper correlation, and to reveal the missing zones in the 
previously described Cretaceous-Tertiary sections. 

This rapid review of the most important Upper Cretaceous-Lower Tertiary sections 
in Egypt summarizes the nature, classification and distribution of these rocks and 
their varied interpretation by different authors. It also shows the difficulties 
encountered in the stratigraphical analysis of these strata, and the several problems 
which were left unsolved. Comparison with the succession in the Esna-Idfu region 
shows clearly that the boundary between the Campanian and the Maestrichtian 
could not be decided, that the Maestrichtian could not be defined or classified, that 
the Mesozoic-Cainozoic boundary could not be traced, that the Danian could not be 
clearly defined, that the various divisions of the Paleocene were very much confused, 



44 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

and that the Paleocene-Eocene boundary was differently interpreted by different 
authors. 

C. Summary of the Succession 

The Upper Cretaceous-Lower Tertiary succession in the Esna-Idfu region is 
naturally divided into four main lithological units which are easily recognizable in the 
field and are arranged from the base upwards as follows : 

i. A lower arenaceous unit composed mainly of sandstones, and passing into 
variegated shales at its top through various intercalations of shaly sand- 
stones, sandy shales, shales and clays. The base of this unit is nowhere 
visible in the region, but can be seen unconformably overlying the basement 
complex at a distance of about 75 kms. to the east and about 100 kms. to the 
south. This unit is about 500 m. thick, but a maximum thickness of 80 m. 
only crops out in the Esna-Idfu region. 

2. An alternating succession of broadly extended phosphate lenses (approaching 

the form of regular beds), marl with flint nodules, chert bands and oyster 
limestone, which has a maximum thickness of about 10 m. 

3. A lutaceous unit about 240m. thick, composed mainly of shales, but with marly 

and chalky intercalations. 

4. An upper calcareous unit composed of a small thickness of calcareous shales at 

its base, passing upwards into chalky, marly and siliceous limestones which 
constitute the main part of this unit. Only the basal 60 m. or so crop out in 
the Esna-Idfu region, while to the north and west the unit reaches a thick- 
ness of about 340 m. 

The lowermost sandstone unit, which was commonly referred to as " the Nubian 
sandstone " was recognized by Youssef (1957), in the Kosseir area, as a formation and 
was named the " Nubia sandstone ". 

Ghorab (1956) considered the variegated shales overlying the Nubia sandstone and 
underlying the lowermost phosphate bed in the Kosseir area as a separate formation 
and named it the " Quseir formation ". Youssef (1957) suggested the name " Kossier 
variegated shales " for the same formation. However, because of the small thickness 
outcropping of both the sandstones and the shales in the Esna-Idfu region, and because 
the two facies pass imperceptibly into one another, these variegated shales are here 
included within the Nubia sandstone, and the two facies are considered as one forma- 
tion which is here collectively termed " the Nubia sandstone and variegated shale ". 

A succession of phosphates, marls and limestones overlies the Nubia sandstone and 
variegated shale, with a general conformable relationship, except for local thinning 
out, diastems or even disconformities. This succession, although of a comparatively 
small thickness (not exceeding 10 m.), has a considerable lateral extent, and forms a 
sharply distinctive and a conveniently mappable rock unit. Thus it is here consider- 
ed as a distinct formation and assigned the name " Sibaiya phosphate ". Ghorab 



LITHOSTRATIGRAPHICAL UNITS 


BIOSTRATIGRAPHICAL 


UNITS 




AGE 


GROUP 


FORMATIONS AND MEMBERS 


PLANKTONIC FORAMINIFERAL UNITS 


MACROFAUNAL UNITS 


i 


1 


1 


2 
u 
i- 

> 


ASSEMBLAGES 


ZONES AND SUBZONES 


ASSEMBLAGES 


ZONES AND SUBZONES 


t 
-l O 


IHE8ES UHES10NE 

AND 

CALCAREOUS 

SHALE 


IHEBES LIMESTONE 


VERY RARE PLANKTONIC FORAMINIFERA 

I Flood o! Hummuliles Dperculina, Assilina, Discocyclino, etc.| 


ASSEMBLAGE WITH 

HO 

AMMONITES 


Lucina theboico Zone 




1 


t 


( 

> 
a: 
< 

H 

cc 

LU 


THEBES CALCAREOUS SHALE 


HIGHLY RUGOSE GLOBIGERINA / 
HIGHLY RUGOSE AND /OR KEELED 
GLOOOR0TAL1A 


Globorololm wilcoiensis Zone 


I except lor rare dworled lorms) 


Q. 

o 

cr 
O 

< 

-z. 

in 


QWAIHA SHALE 


UPPER OWAINA SHALE 


GLOBIGERINA /SHARPLY- KEELED 
GLOBOROTALIA 


Globorotolio velastoensis 


Globorolalia aequo / 
Globoiololla esnaensis 
Subzone 




5 


1 


MIDDLE DWAINA CHALK 


Oslrea hypoplera Zone 


Globorololio pseudomentirdu Subzone 


LOWER DWAINA SHALE 


GL0BIGER1NA / TRUNCATED GLOODRDTALIA 


Clobarololia unqulola Zone 




Coryosmilio granoso Zone 




HEERSIM 




GL0BIGER1HA / ROUNDED GLOBORGIAUA 


Globorotolio compresso / Globiqermo doubjergensis Zone 


: : '.'-': : ; 


DANUN 


SHARAWNA SHALE 


UPPER SHARAWNA SHALE 


GLOBOTRUNCANA / 
RUG0GL0B1GERINA/ 
ABATHOMPHALUS / 
HEOBERGELLA 

t 


Globolruncona esnehensis Zone 


L1BYC0CERAS/ 
BACULITES 
ASSEMBLAGE 


Pecten IChlomysl 
mayereyman 


Libycoceres berisensis Subzone 


1 


5 


+ 


O 
W 

u 
< 

in 
a: 
U 

♦ 


MIDDLE SHARAWNA MARL 


Globolruncana gunsseri Zone 


Peclen (CJ mayereyman Sutaiwe 


I 


LOWER SHARAWNA SHALE 


Globolruncono formcalo Zone 


Terebralulino gracilis Subzone 


1 


0- 

o 

O 

< 

m 

1 


SI8AIVA PHOSPHATE 


VERY RARE PLANKTONIC FORAMINIFERA 


Lopha villei Zone 


1 


+ 


NUBIA SANDSTONE AND 
VARIEGATED SHALE 


NO FORAMINIFERA 


Zone with no mocrolauno 
leicepl lor rare plant and vertebrate remains | 


1 ? 



y of the various I.itho- and [jio*ir;iliKr;i|.int.-il units of the Upper 



x the Esna-Idfu Iiec 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 45 

(1956) considered similar phosphate deposits in Kosseir area as a formation and 
named it " the Duwi formation", nevertheless the present phosphate deposits 
cannot be assigned to the same formation, as they are comparatively much reduced in 
thickness. The " Sibaiya phosphate " either represents a dwarfed " Duwi forma- 
tion " or only corresponds to a part of that formation. Until the two formations are 
precisely correlated, it is advisable to treat them separately. 

The thick shale succession, which conformably overlies the Sibaiya phosphate 
formation, and which is conmmoly referred to as the " Esna shales ", was recognized 
by Ghorab (1956) as a formation which he named the " Esna formation " and divided 
into three main members from the base upwards as follows : the " Dakhla ash-grey 
shale member ", the " snow-white Ananchytes ovata chalk member ", and the 
" Kharga paper shale member ". However, the present study shows that this thick 
shale succession is actually a group of rock units naturally divided into two distinct 
formations separated by a marked break and a well developed conglomerate. The 
lower formation is here named " the Sharawna shale ", with its type section in the 
Wadi El-Sharawna area, it has a thickness of about 120 m., and is proved to be of 
Maestrichtian age. It includes three main members, a lower shale, a middle marl and 
an upper shale member, the top part of which is truncated by a disconformity. 

The upper formation is here named " the Owaina shale ", with its type section in 
Gebel Owaina, it also has a thickness of about 120 m. and is proved to be of Paleocene 
age ; it includes two shale members separated by a middle chalk member. Its lower 
limit is marked by the disconformity and its upper underlies the " Thebes calcareous 
shale ". 

The uppermost succession of calcerous shale, shaly limestone, and limestone is here 
assigned to the " Thebes formation ". However, the lower calcareous shale is 
distinguished from the overlying " Thebes limestone " as a separate member of the 
same formation and is given the name " Thebes calcareous shale " although it has 
been wrongly assigned by various authors to the Esna shale. 

These different rock units are summarized in Text-figs. 5 and 8, their fossil content 
is listed in Text-figs. 16 and 17 and their respective ages are discussed below. The 
detailed lithostratigraphy of the succession and the lateral variation in the various 
rock units are discussed elsewhere (El-Naggar in manu.), and the main sections 
examined are correlated in Text-fig. 7. 

D. Discussion of the Age 

(1) The Nubia Sandstone and Variegated Shale Formation 

The Nubia sandstone and variegated shale could not be assigned a definite age 
because of its scanty fossil content. However, as the formation is conformably over- 
lain (in places) by the Sibaiya phosphate formation which is here considered as 
Upper Campanian, and as the upper part of the Nubia formation contains rare 
vertebrate remains which are identical to those of the overlying Sibaiya formation, 
this upper part, at least, should be regarded as only slightly older than the overlying 



I" UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

" Sibaiya formation ". 3 Moreover, as no stratigraphical breaks were observed within 
the part of this formation, outcropping in the Esna-Idfu region, the author is 
inclined to include the outcropping part of the Nubia formation in the Esna-Idfu 
region, in the Campanian. However, as there is no direct evidence, the age of this 
formation is here considered to be Campanian and ? pre-Campanian. 

(2) The Sibaiya Phosphate Formation 

Despite the fact that the Sibaiya formation did not yield any identifiable plank- 
tonic Foraminifera, and that its macrofauna does not provide a direct means for 
correlation with the type sections in Europe, it is here considered to belong to the 
Upper Campanian for the following reasons : 

(a) Blanckenhorn (1921) and Hassan (1956) recorded Bostrychoceras polyplocum 

Roemer, an index fossil for the Upper Campanian in its type section and 
elsewhere, from the same formation in other parts of Egypt, and with a 
typically similar association of fauna. 

(b) The Sibaiya formation is conformably overlain by the " lower Sharawna shale 

member ", which is characterized by the first appearance of Terebratulina 
gracilis Schlotheim, an index fossil for the base of the Maestrichtian. 
Terebratulina gracilis was also recorded from Lower Maestrichtian strata 
conformably overlying the " Bosytrchoceras polyplocum s.l. Zone " in Germany 
(Schmid, Hiltermann & Koch 1955) ; in Palestine (Parnes 1956) ; in Holland, 
Belgium and in the Aquitaine Basin of France (Upper Cretaceous Stratigraphic 
Commission, International Geological Congress ; in Reiss 1962 : 4). 

(c) Most of the recorded Pelecypod fauna was considered by the various authors 

(including Coquand, the creator of the Campanian substage) to be mainly of 
Campanian age, although a few forms may continue into the overlying basal 
Maestrichtian. On the other hand, the varied vertebrate fauna of the 
Sibaiya phosphate formation occurs in Europe in strata of Coniacian to 
Campanian age (e.g. Siegfried 1954, 1956). 

(d) The Sibaiya formation is conformably overlain by two successive planktonic 

foraminiferal zones which are considered, by correlation with similar zones 
in other parts of the world (Text-figs. 5, 6), to represent the Lower and 
Middle Maestrichtian respectively. 

(e) In spite of its small thickness, the Sibaiya formation, as a chemically formed 

deposit, represents a relatively long period of time and an enviroment of 
deposition, completely different from that of the overlying shales. 

(f) The Sibaiya phosphate formation can be correlated with similar deposits 

in the Kharga and Dakhla Oases, Qift and Quene areas, Kosseir and Safaga 
districts and with corresponding deposits in the Middle East and North 
Africa which are regarded as Upper Campanian. 

3 The close similarity of the vertebrate remains in these two formations suggested their inclusion in 
one group of rock units, here termed the " Nubia group ", and is discussed elsewhere (El-Naggar, 
in manu.). 



in the esna-idfu region, nile valley, egypt 47 

(3) The Sharawna Shale Formation. 

The Sharawna shale formation is considered to be of Maestrichtian age for the 
following reasons : 

(a) It conformably overlies the Upper Campanian " Sibaiya phosphate forma- 

tion ". 

(b) Eleven meters above the base of the formation, a marly band flooded with 

Terebrahtlina gracilis Schlotheim, Isocardia (Isocardia) chargehensis Mayer- 
Eymar and Pecten (Chlamys) mayereymari Bullen-Newton, as well as with 
several other macro- and microfossils, was discovered. Terebrahtlina 
gracilis marks the base of the type Maestrichtian in Holland, and of the 
Maestrichtian rocks in Belgium and in the Aquitain Basin of France (the 
Maestricht-Committee of the Sub-Committee on the Upper Cretaceous 
Stratigraphic Commission, International Geological Congress ; in Reiss 
1962). It also marks the base of the Maestrichtian in Germany (Schmid, 
Hiltermann & Koch 1955) and in Palestine (Parnes 1956). 

(c) The lower part of the Sharawna shale formation i.e. the Lower Sharawna 

shale member, is flooded with a rich planktonic foraminiferal fauna 
(Text-figs. 9-1 1, 16) which substantiates its Lower Maestrichtian age and 
correlates it with the Lower Maestrichtian in various parts of the world 
(Text-fig. 6). 

This fauna characterises a particular zone which is here termed the Globotruncana 
fornicata Zone. Noteworthy among the species characteristic of this zone are 
members of the Globotruncana fornicata group and most of the members of the 
Globotruncana stuarti group, the last representatives of which mark the Lower 
Maestrichtian in most parts of the world, (e.g. Cita 1948 ; Tilev 1951, 1952 ; 
Drooger 1951 ; Bolli 1951, 19570 ; Noth 1951 ; Sigal 1952 ; Dalbiez 1955 ; Gandolfi 
1955 ; Pozaryski & Witwicka 1956 ; Bronnimann & Brown 1956 ; and Pessagno 
i960). 

Also of importance in this zone are : Globotruncana area, G. gagnebini, G. fareedi, 
G. havanensis and Rugoglobigerina rugosa, which are known to be restricted to the 
Maestrichtian in different parts of the world (see Bronnimann & Brown 1956 ; 
Tilev 1951, 1952 ; Bolli 1957a ; Berggren 1962, etc.), as well as Globotruncana 
leupoldi, G. aegyptiaca aegyptiaca, G. tricarinata tricarinata and G. ventricosa, which 
characterize older strata, but range through the Lower Maestrichtian. 

(d) The " Middle Sharawna marl member " is marked by the first appearance of 

Globotruncana gansseri ganserri Bolli at its base, and this, together with 
its other subspecies, floods the whole unit and the lower part of the overlying 
shale member, constituting a particular faunal zone, here termed the "Globo- 
truncana gansseri zone ". Analysis of the stratigraphical ranges of the 
various members of this zone, substantiates its Middle Maestrichtian age 
and correlates it with corresponding strata elsewhere. Globotruncana 
gansseri gansseri Bolli, the index fossil of the zone, was recorded as 



48 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

flooding the Middle Maestrichtian of various parts of the world, with rare 
occurrence in the upper part of the Lower Maestrichtian and in the basal 
part of the Upper Maestrichtian (Bolli 1951, 1957a, 19596 ; Nakkady & 
Osman 1954 ; Gandolfi 1955 ; Dalbiez 1955 ; Bronnimann & Brown 1956 ; 
Olsson i960 ; Pessango i960 ; and Berggren 1962). This zone is also 
flooded with forms of definite Maestrichtian age such as Globotruncana 
contusa contusa, G. contusa patelliformis, G. area, G. conica, G. esnehensis, 
G.fareedi, G. gagnebini, G. lugeoni, G. stuarti parva, G. aegyptiaca aegyptiaca, 
G. aegyptiaca duwi, G. havanensis, Abathomphalus intermedia, Rugoglobi- 
gerina rugosa, R. pustulata, R. pennyi, R. macrocephala, R. loetterli, R. 
glaessneri, Hedbergella monrnouthensis, H. petaloidea, H. mattsoni, H. hessi 
hessi and H. hessi compressiformis. 

Some of these species were recorded from the type Maestrichtian (Hofker 
1962a), from the Maestrichtian rocks underlying the type Danian (Troelsen 
1955 ; Berggren 1962) and from the Maestrichtian rocks of various parts of 
the world. (See the discussion under each of the above-mentioned species.) 

(e) The Upper Sharawna shale member conformably overlies the " Middle 
Sharawna marl member ", while its top is truncated by a marked strati- 
graphical break. A conglomerate with reworked Maestrichtian ammonites, 
gastropods and lamellibranchs, together with a typical Upper Danian 
fauna, marks this break and indicates the dawn of the Cainozoic era. 

Analysis of the planktonic foraminiferal content of the " Upper Sharawna shale 
member " has proved its Middle to Upper Maestrichtian age. It has also proved 
that its lower part constitutes the top of the Middle Maestrichtian G. gansseri zone, 
while its upper part constitutes the lower part of the Upper Maestrichtian G. esnehen- 
sis zone. Worthy of mention in the latter zone are the following species : 

Abathomphalus mayaroensis, A. intermedia, Globotruncana contusa contusa, G. 
contusa patelliformis, G. esnehensis, G. gagnebini, G. aegyptiaca aegyptiaca, G. 
aegyptiaca duwi, G. mariei, G. havanensis, G. stuarti parva, Rugoglobigerina rugosa, 
R. rotundata, R. pustulata, R. pennyi, R. macrocephala, Trinitella scotti, Hedbergella 
monrnouthensis, and H. petaloidea. These were partly recorded from the Upper Maes- 
trichtian at its type section (Hofker 1962a), from the Upper Maestrichtian rocks below 
the type Danian (Berggren 1962 and Troelsen 1955), and from the same horizon 
elsewhere (Bronnimann 1952a ; Bronnimann & Brown 1956 ; Bolli 195 1, 1957a, 
19596 ; Dalbiez 1955 ; Pessango i960, 1962, etc.). However, the fact that in the 
succession studied, the Upper Maestrichtian part is represented by a comparatively 
small thickness of strata (about 13 m. only), and that reworked Upper Maestrichtian 
macrofossils occur in the conglomeratic band which forms the base of the Upper 
Danian strata above, clearly indicates that the uppermost Maestrichtian is missing. 
Thus the upper part of the " Upper Sharawna shale member " corresponds to the 
lower part of the Upper Maestrichtian only. 

The macrofauna of the Sharawna shale formation correlates it with equivalent 
Maestrichtian strata in Egypt, the Middle East and North Africa (Parnes 1956 ; 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 49 

Hassan 1956 ; Youssef 1957 ; Hermina, Ghobrial & Issawi 1961). Its planktonic 
Foraminifera correlate it with the type Maestrichtian (Hofker 1962a), with the 
Maestrichtian rocks below the type Danian (Berggren 1962 and Troelsen 1955) and 
with the Maestrichtian in various parts of the world (Text-fig. 6). However, the 
disconformity separating the Maestrichtian Sharawna shale formation from the 
overlying Paleocene was always overlooked in the past, and the stratigraphical 
sequence as well as the chronological succession of life in this part of the geological 
column was never completely understood. As a result, various authors (e.g. Hume 
1911, 1912, followed by most stratigraphers) tended to lump the Sharawna shale 
formation, either partly or completely, together with the overlying Lower Owaina 
shale member under the term " Lower Esna shales ", and considered these shales 
with the overlying chalk bed as of Danian age. On the other hand, Nakkady (1959) 
described as " Lower Esna shale " in the Kharga Oasis, a succession of Paleocene 
shales which is here considered to be identical with the Lower Owaina shale 
member. 

Thus, it is evident that the classification of the Esna shale into lower and upper 
units as suggested by Hume (1911, 1912) and followed by various authors is incorrect, 
and should be replaced by the classification suggested here. Again, it is worth 
noting that the term Dakhla shale, introduced by Ghorab (1956) as a member of his 
Esna formation, to substitute for the " Ashen grey paper shales " of some authors, 
or the " Lower Esna shale " of others, and which was raised to formational rank by 
Said (1961) is also incorrect. The " Dakhla shale " as originally designated and 
interpreted in the present study, includes the Maestrichtian " Sharawna shale ", the 
conglomerate separating it from the overlying Paleocene " Owaina shale ", and the 
lower part of the latter formation. These varied lithological and palaeontological 
units which are clearly separated by a marked break, cannot be treated as one 
formation. Thus the term " Dakhla shale " is here dropped and the classification 
of the Esna group into a lower " Sharawna shale " formation and an upper " Owaina 
shale " formation is suggested. 

The " Sharawna shale " is equated on lithological and palaeontological grounds 
with similar successions in both the Dakhla and the Kharga Oases (Western Desert) 
and in the Kosseir and Safaga areas (Red Sea Coast). It is proved to have a wide 
geographical extent in Egypt, although it becomes gradually more calcareous when 
followed northwards until completely replaced by chalk. 

(4) The Owaina Shale Formation. 
This formation is considered to be of Paleocene age, for the following reasons: 

(a) It disconformably overlies the Maestrichtian " Sharawna shale ", and 

underlies the Lower Eocene " Thebes formation ". 

(b) Its base is marked by a conglomerate with reworked Maestrichtian, and 

Danian faunas, and its upper part coincides with the top of the Globorotalia 
velascoensis Zone which is taken to mark the end of the Paleocene in vari- 
ous parts of the world (see Text-fig. 6). 



50 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

(c) Its basal part contains a rich fauna of the Globorotalia compressajGlobigerina 

daubjergensis Zone which correlates it with the type Danian (Bronnimann 
1953 ; Reichel 1953 ; Troelsen 1957 ; Loeblich & Tappan 1957a, b ; and 
Berggren 19606, 1962) and with the Danian elsewhere (Bolli 19576, 19596 ; 
Loeblich & Tappan 1957a, b ; Bolli & Cita 1960a, b ; Olsson i960 ; Hay 
i960 ; Leonov & Alimarina 1961). 

The abundance of Globorotalia compressa (Plummer) in the Danian part 
of this succession, which is very much reduced in thickness (maximum of 
about 17 m. only), clearly proves that it represents the Upper Danian only 
(see Berggren 19606, 1962), and that both the Lower and Middle Danian are 
missing. 

(d) This Upper Danian part is followed by a zone devoid of both Danian index 

species and of those characteristic of the Upper Paleocene. This zone is 
marked by the first appearance of the truncated Globorotalia species and 
by a flood of the Globorotalia angidata group. It is here named the Globo- 
rotalia angulata Zone and is considered, on the basis of its stratigraphical 
position, to be of Middle Paleocene age. 

(e) The middle and upper members of the Owaina shale formation coincide with 

the Globorotalia velascoensis Zone which is of Upper Paleocene age as 
discussed above. However, it is worth noting that the first appearance of 
Globorotalia velascoensis does not precisely coincide with the base of the 
intercalated chalk bed (the Middle Owaina chalk member), but occurs 
slightly below it in a band of calcareous shale with thin chalky bands 
which is considered transitional to the Middle Owaina chalk member. 

(f) The Owaina shale formation is overlain by the Globorotalia wilcoxensis 

Zone of Lower Eocene age (see Text-figs. 5 and 6). 

Thus it is evident that the Owaina shale formation is of Paleocene age, that its 
basal part corresponds to the Upper Danian in its type section and elsewhere, and 
that its upper part correlates with the known Upper Paleocene in various parts of 
the world. However, in view of the confusion about the planktonic foraminiferal 
content of the various stages of the Paleocene (see p. 25 et seq.), the author decided 
not to use the known Paleocene stage names (e.g. Montian, Thanetian, Landenian, 
Seelandian, Ilerdian) 4 , but to divide the Paleocene into three major divisions, lower, 
middle and upper, on the basis of its three planktonic foraminiferal zones, as discus- 
sed above (see pp. 24-31) and summarized on Text-figs. 5 and 6. 

The planktonic Foraminifera of the Owaina shale formation correlates it with 
known Paleocene sections elsewhere in the world (Text-fig. 6), and its macrofossils 
clearly relate it to similar successions in Egypt (Zittel 1883 ; Quaas 1902 ; Wanner 
1902 ; Oppenheim 1902 ; Hume 191 1 ; Cuvillier 1937a, 6 ; Youssef 1955, 1957 ; 
Hassan 1956 ; Hermina et al., 1961. However, the misunderstanding of the true 
nature of the Cretaceous-Tertiary contact in Upper Egypt introduced by Zittel (1883) 

4 See footnote 2 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 51 

and repeated by Faris (1947) has completely confused the identity of the Paleocene 
in Egypt. The fact that the stratigraphical break was overlooked, led authors to 
assign the Owaina shale formation either partly or completely to the Danian. It 
also led, as mentioned above, to the erroneous classification of the Esna shale into a 
lower and upper member, separated by the middle chalk. As a result, the lower 
Owaina shale member was lumped together with all or part of the underlying 
Sharawna shale under the name " Lower Esna shale ". The latter, together with 
the overlying chalk bed were assigned by most authors to the Danian, while others 
also included the overlying shale succession in the " Danian ". 

Analysis of the various Paleocene successions described by previous authors who 
wrongly assigned them to the Cretaceous and/or the Tertiary, shows the widespread 
nature of the Owaina shale formation, the persistence of its lithological units and the 
great extent of the Paleocene transgression over the Egyptian territory, (which 
possibly represents the greatest transgression in the geological history of Egypt). 
It also shows clearly the applicability of the term " Owaina shale " over vast areas 
in Egypt, although the formation becomes progressively more calcareous towards 
the north. 

(5) The Thebes Limestone and Calcareous Shale Formation. 

This formation is considered to be of Lower Eocene age for the following reasons : 

(a) It conformably overlies the " Upper Owaina shale member " which is 

proved to be of uppermost Paleocene age. 

(b) Its lower member, the " Thebes calcareous shale ", contains a rich planktonic 

foraminiferal fauna which correlates it with the Lower Eocene in various 
parts of the world (Text-fig. 6). Among these, Globorotalia wilcoxensis 
Cushman & Ponton is worth mentioning as it is taken as a guide fossil for 
the Lower Eocene, in spite of its occurrence in the uppermost part of the 
underlying Paleocene (see discussion under this species). Also of import- 
ance in this assemblage is Globorotalia bollii {^Globorotalia rex of Bolli 
1957&) which is considered by various authors as the zone marker of the 
Lower Eocene (see Text-fig. 6). 

(c) The lithology and fauna of the " Thebes limestone member " of the Esna- 

Idfu region correlate it with the " Thebes limestone " in its type section 
(Delanoue 1868 ; Said i960) and its equivalents elsewhere, which were 
generally assigned to the Lower Libyan. Such characteristic lithology 
and fossil content are almost uniform over a vast extent of the Egyptian 
territory, constituting a particular rock unit which is generally assigned to 
the Lower Eocene (Zittel 1883 ; Cuvillier 1930, etc.). 

(d) Although washed samples from the " Thebes limestone member " of the 

Esna-Idfu region did not yield any identifiable planktonic Foraminifera 
(possibly because of its silicification), samples from the type section at 
Thebes were recorded by Said (i960) to contain a few planktonic forms. 
These, although misidentified, support the Lower Eocene age of the type 
Thebes limestone. 



52 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Thus, it is evident that the Thebes limestone and calcareous shale formation 
is of Lower Eocene age. However, the controversy about the stratigraphical 
relationship between the Ypresian and Cuisian stages, necessitates the avoidance of 
the use of these terms in Lower Eocene stratigraphy, until their chronological 
relationship is clarified. 5 For example, while some authors tended to use the Ypre- 
sian followed by the Cuisian within the Lower Eocene, Hottinger & Schaub (i960) 
used the Cuisian as the Lower Eocene, and Feugueur (1962) equated the Cuisian 
with the Upper Ypresian. 



IV. PALAEONTOLOGY 

A. The Macrofauna 

Systematic studies of the macrofossils of the Upper Cretaceous-Lower Tertiary 
rocks of Egypt were carried out by Zittel (1883), Quass (1902), Wanner (1902), 
Oppenheim (1902), Fourtau (1899-1921), Peron & Fourtau (1904), Stefano (1912- 
1919), Priem (1914) Greco (1915-1918), Stefanini (1918-1919) 6 and Abbass (1962). 

In the present study, macrofossils are used for correlation with similar successions 
previously zoned on the basis of macrofossils alone. However, most of these fossils 
are unknown outside the Tethyan region and their ranges have been much disputed 
in the past. Study of the associated planktonic Foraminifera in the Esna-Idfu 
region has helped to define the ranges of the macrofossils in terms of the foraminiferal 
zonation, and has thus cleared up some of the confusion. 

One hundred and forty two macrofossil species are identified and their ranges 
considered (Text-fig. 17). However, no attempt has been made to carry out a 
systematic study of these macrofossil species which are only listed alphabetically 
within their respective phyla (Text-fig. 17). 

Consideration of the ranges of these macrofossils, has led to the recognition of five 
major faunal zones and three subzones, in addition to a non-fossiliferous zone at the 
base, and a zone devoid of macrofossils towards the top of the succession (Text-figs. 
5, 8 and 17). These zones and subzones are correlated with the corresponding 
planktonic foraminiferal zones and subzones in Text-fig. 5 ; they are arranged from 
the base upwards as follows : 

1. A non-fossiliferous zone. 

2. The Lopha villei Zone. 

3. The Pecten (Chlamys) mayereymari Zone. 

(a) The Terebratulina gracilis Subzone. 

(b) The Pecten (Chlamys) mayereymari Subzone. 

(c) The Libycoceras berisensis Subzone. 
oox\a^\a^/v'\a^wvvv\a^^vvv\a^/v\A/ Disconformity wuwwwv^wwv 

6 See footnote 2 
• See Keldani 1941 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 53 

4. The Caryostnilia garnosa Zone. 

5. The Ostrea hypoptera Zone. 

6. A non-megafossiliferous zone. 

7. The Lucina thebaica Zone. 

In view of the restricted geographical distribution of most of these macrofossils, 
the above-mentioned zones may be regarded as of local importance only. Neverthe- 
less, analysis of previously described Upper Cretaceous-Lower Tertiary successions 
in Egypt, North Africa and the Middle East points to the possible existence of these 
zones at corresponding horizons all over this region. Some of the index fossils of 
these zones, e.g., Lopha villei and Libycoceras spp. (L. ismaeli Zittel, L. chargense 
Blanckenhorn and possibly L. phosphaticus Awad & Naiem and L. berisensis Awad & 
Naiem) are known to flood corresponding horizons in North Africa, (Laffitte 1934, 
1939), while the same species, in addition to Pecten (Chlamys) mayereymari Bullen- 
Newton and Terebratulina gracilis Schlotheim, are recorded in abundance in similar 
formations in Palestine (Parnes 1956). Thus, although it is understood that these 
macrofossil zones are not of the world-wide importance of the corresponding plank- 
tonic foraminiferal zones, they may be successfully applied in North Africa and the 
Middle East. The value of these zones is now enhanced by the fact that they have 
been defined in the light of the corresponding planktonic foraminiferal zonation, 
and can thus be used in the absence of planktonic Foraminifera. 

B. The Planktonic Foraminifera 

The Foraminifera of the Upper Cretaceous and Lower Tertiary rocks of Egypt 
have been dealt with by Nakkady (1949, 1950, 1951a, 1952, 1955, 1957, 1959). 
Nakkady & Osman (1954), Osman (1954, 1955a, b, c), Le Roy (1949, 1953), Omara 
(1954, 1955, 1956), Said & Kenawy (1956), Said (i960) and Said & Kerdany (1961). 
However, very little has been published on the planktonic Foraminifera in spite of 
their abundance, and reliance on the benthonic Foraminifera in stratigraphical 
zonation has led to a great deal of discrepancy and confusion. In this connection 
Bolli (1957a : 62) stated that " The complete change of the planktonic foraminiferal 
fauna between the Upper Cretaceous Guayaguayare formation and the Paleocene- 
Lower Eocene Lizard Springs formation, is not followed by the benthonic Foramin- 
ifera . . ., as many as about two-thirds of the benthonic species known in the Upper 
Cretaceous continue into the Paleocene-Lower Eocene. In cases where only 
benthonic Foraminifera are present, it may become difficult, therefore, to determine 
whether a fauna is of Upper Cretaceous or Paleocene age ". The same is true in 
Egypt, where it has been found essential to establish the stratigraphy of the Upper 
Cretaceous-Lower Tertiary period on the basis of planktonic Foraminifera which 
were only briefly dealt with before, and were very much confused and misidentified. 

Although Nakkady (1951a) was one of the earliest micropalaeontologists to 
emphasize the value of planktonic Foraminifera in the zonation of the Cretaceous- 
Tertiary transition period, he only discussed them very briefly in his study on the 
Foraminifera of the Esna shale. Nakkady (1950, 1951a) recorded the occurrence of 
the following planktonic Foraminifera from the Maestrichtian-Lower Eocene 



54 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

succession of six widely-separated sections in Egypt : Globotruncana aegyptiaca 
Nakkady, G. aegyptiaca var. duwi Nakkady, G. aegyptiaca var. /. Nakkady, G. area 
(Cushman), G. area (Cushman) var. esnehensis Nakkady, G. cretacea Cushman, 
G. pseudocretacea Nakkady ; Globigerina bulloides d'Orbigny, G. cretacea d'Orbigny, 
G. cretacea d'Orbigny var. esnehensis Nakkady, G. linaperta Finlay, G. quadrata White ; 
Globorotalia colligera (Schwager), G. colligera (Schwager) vavxrassaformis (Galloway 
& Wissler), G. crassata (Cushman) var. aequa Cushman & Reuz, G. deceptoria 
(Schwager), G. simidatilis (Schwager), and G. velascoensis (Cushman). 

However, examination of his specimens in the British Museum (Natural History), 
London, showed clearly that: 

i. G. aegyptiaca var. I is an entirely single-keeled form which belongs to the 
Globotruncana gansseri group. 

2. Typical forms of Globotruncana stuarti stuarti (de Lapparent) were included 

within his G. area (Cushman), and thus the former species was not recorded 
in spite of its abundance in his material and in the Egyptian Maestrichtain 
rocks in general. 

3. G. area var. esnehensis is a distinct species from G. area (Cushman) as realized 

by Nakkady & Osman (1954), and is thus treated separately. 

4. Specimens of G. cretacea Cushman actually belong to Globotruncana stuarti 

stuartiformis Dalbiez, G. gagnebini Tilev, and G. aegyptiaca aegyptiaca 
Nakkady. 

5. G. pseudocretacea sp. nov. is probably Globotruncana gagnebini Tilev. 

6. G. bidloides d'Orbigny includes some forms related to Globigerina bacuana 

Khalilov and others, which though indeterminable, are completely different 
from the form of d'Orbigny. 

7. Forms described as G. cretacea d'Orbigny are actually Globorotalia trinida- 

densis Bolli G. compressa (Plummer) and G. cf. pseudobulloides (Plummer). 
The form described by d'Orbigny is a true Globotruncana, not a Globigerina, 
and does not cross the Campanian-Maestrichtian boundary. 

8. The holotype of G. cretacea var. esnehensis is actually Globigerina mckannai 

White, while the paratype is a transitional stage between Globorotalia 
pseudobulloides (Plummer) and G. trinidadensis Bolli. 

9. G. linaperta Finlay is Globigerina triloculinoides Plummer. 

10. Globigerina quadrata White includes Globorotalia irrorata Loeblich & Tappan, 

G. tribulosa Loeblich & Tappan, Globigerina triloculinoides Plummer, 
besides Globorotalia quadrata (White). 

11. Specimens of G. colligera (Schwager) belong to Globorotalia cf. subbotinae 

Morozova, G. cf. aequa Cushman & Renz, and G. cf. wilcoxensis Cushman 
& Ponton. The form described by Schwager was recorded from younger 
strata and is not well known. Until the holotype is refigured and rede- 
scribed in more detail, it is not really known what is meant by G. colligera 
(Schwager) . 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 55 

12. G. colligera (Schwager) var. crassaformis (Galloway & Wissler) is G. wilcoxensis 

Cushman & Ponton. 

13. G. crassata var. aequa Cushman & Renz includes Globorotalia rex Martin, 

G. aequa Cushman & Renz and other unknown forms. 

14. G. deceptoria (Schwager) includes various forms of Globigerina and Globorotalia 

e.g. Globorotalia aequa Cushman & Renz, G. wilcoxensis Cushman & Ponton, 
and G. whitei Weiss ; Globigerina stonei Weiss, and G. valascoensis Cushman. 

15. G. simulatilis (Schwager) includes Globorotalia rex Martin, G. occlusa Loeblich 

& Tappan, G. velascoensis parva Rey, G. cf. pseudoscitula Glaessner, G. 
emilei sp. nov., and G. cf. angulata abundocamerata Bolli. Again, G. 
simulatilis was recorded from younger strata, and its holotype needs to be 
redrawn and redescribed in more detail. 

16. G. velascoensis (Cushman) includes G. velascoensis velascoensis (Cushman), 

G. cf. angulata angulata (White), G. cf. angulata abundocamerata Bolli, 
G. cf. pseudoscitula Glaessner, and G. cf. occlusa Loeblich & Tappan. 

Nevertheless, on the basis of these few planktonic forms, Nakkady established 
three biozones in the Mesozoic-Cainozoic transition beds of Egypt : a Globotruncana 
Zone of Maestrichtian age, a Globorotalia Zone of Paleocene age and an intervening 
Buffer Zone of Danian age, distinguished by the complete absence or extreme 
scarcity of both Globorotalia and Globotruncana. 

Nakkady's pioneering attempt was mainly based on genera, and as the planktonic 
Foraminifera are known to exhibit an abrupt change in their generic composition at 
the Cretaceous-Tertiary boundary all over the world, his Maestrichtian-Danian 
boundary was correctly drawn. However, he neither recognized the Tertiary 
character of the Danian fauna, nor the obvious stratigraphical break between the 
Upper Cretaceous and the basal Tertiary, which can be easily seen on his chart 
(1951a), where his Buffer zone was shown to vary greatly in thickness. Moreover, 
in his later studies, Nakkady confused the limits between the various stages of the 
Paleocene and between the Paleocene and the overlying Eocene. Nevertheless, his 
faunal sequence (a Globotruncana Zone, followed by a Buffer or Globigerina Zone and 
a Globorotalia Zone, for the Maestrichtian, Danian and Paleocene respectively) has 
since been observed in many parts of the world and has been used as a basis for the 
precise zonation of the Cretaceous-Tertiary succession. 

Nakkady (1959) recorded the following planktonic Foraminifera from what he 
considered as Maestrichtian-Montian of the Um Elghanayem section, Kharga Oasis, 
Egypt : Globotruncana aegyptiaca Nakkady, G. quadrata Nakkady & Osman ; 
Globorotalia angulata (White), G. crassata var. aequa Cushman & Renz, G. deceptoria 
(Schwager), G. pseudomenardii Bolli, G. quadrata Nakkady & Talaat, G. simulatilis 
(Schwager), G. velascoensis (Cushman) ; Globigerina esnaensis Le Roy, G. mckannai 
White, G. pseudobulloides Plummer, G. quadrata White, and G. triloculinoides 



56 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Plummer. Although he did not figure all his forms, analysis of his figures and 
descriptions showed that : 

1. G. angulata (White) probably belongs to Globorotalia occlusa Loeblich & 

Tappan, while G. quadrata Nakkady & Talaat belongs to Globorotalia 
angulata angulata (White). 

2. G. simulatilis (Schwager) is probably Globorotalia acuta Toulmin. 

3. G. velascoensis (Cushman) is probably G. angulata abundocamerata Bolli. 

4. G. pseudobulloides Plummer is probably a transitional stage between Globoro- 

talia trinidadensis Bolli and Globorotalia pseudobulloides (Plummer) . 

5. G. quadrata White is probably Globorotalia pseudobulloides (Plummer), and his 

G. triloculinoides Plummer is Globigerina triloculinoides parva subsp. nov. 
Moreover, his record of Globigerina quadrata White and G. triloculinoides 
Plummer throughout the Upper Cretaceous-basal Tertiary succession 
points to the possibility that he had lumped apparently similar Rugoglobi- 
gerina and Hedbergella forms with these species and thus extended their 
ranges. 

Nakkady & Osman (1954) briefly discussed the genus Globotruncana in Egypt and 
its value in stratigraphical zonation, basing their discussion on the Maestrichtian 
sections, previously studied by Nakkady (1949, 1950, 1951a, 1952) and on the 
Campanian-Maestrichtian of Qabeliat and Sudr sections, western Sinai. These 
authors described seventeen species and four varieties of Globotruncana, most of 
which were new, but, unfortunately, their descriptions are very short and their 
figures very poor. These forms were cited as follows : Globotruncana aegyptiaca 
Nakkady, G. aegyptiaca var. duwi Nakkady, G. aegyptiaca var. /. Nakkady, G. 
ansarii Nakkady & Osman, G. caliciformis (de Lapparent), G. contusa (Cushman), 
G. cretacea Cushman, G. esnehensis Nakkady & Osman, G. gansseri Bolli, G. globigeri- 
noides Brotzen, G. lapparenti Brotzen, G. pooleyi Nakkady & Osman, G. pseudo- 
fornicata Nakkady & Osman, G. qabeliatensis Nakkady & Osman, G. quadrata 
Nakkady & Osman, G. quadrata var. plata Nakkady & Osman, G. rosetta (Carsey), 
G. sudrensis Nakkady & Osman, G. sudrensis var. parallela Nakkady & Osman, 
G. torensis Nakkady & Osman, and G. ventricosa White. 

The holotypes of these forms need to be re-examined, refigured, and redescribed in 
more detail so that their true identities can be established, and their relationships to 
previously described species decided. 

Le Roy (1953) recorded the following planktonic Foraminifera from the Maestrich- 
tian-Lower Eocene succession of the Maqfi section, Farafra Oasis, Egypt : Globo- 
truncna canaliculata (Reuss) ; Globigerina esnaensis Le Roy, G. pseudotriloba White, 
G. subcretacea Lomnicki ; Globorotalia membranacea (Ehrenberg), G. simulatilis 
(Schwager) and G. velascoensis (Cushman). 

Analysis of his descriptions and figures showed that : 

1. G. canaliculata (Reuss) is most probably Globotruncana area (Cushman). 

2. G. esnaensis Le Roy is a Globorotalia. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 57 

3. G. pseudotriloba White is probably Globigerina linaperta Finlay. 

4. Apparently he had included under G. subcretacea Lomnicki several Hedbergella, 

Globigerinelloid.es, Rugoglobigerina, Globigerina and Globorotalia species, thus 
extending its range from the Maestrichtian to the Lower Eocene. His 
figured specimen is probably a species of Hedbergella or Globigerinelloides, 
but the lack of a side view and the brief description make an accurate 
determination impossible. 

5. G. membranacea (Ehrenberg) probably belongs to Globorotalia emilei sp. nov. 

while G. simulatilis (Schwager) should be assigned to Globorotalia rex Martin, 
and G. velascoensis (Cushman) to G. velascoensis velascoensis (Cushman). 

Said & Kenawy (1956) recorded the following planktonic Foraminifera from the 
Maestrichtian-Lower Eocene succession of the Giddi and the Nekhl sections, north- 
ern Sinai, Egypt : Globotruncana aegyptiaca Nakkady, G. caliciformis Vogler, G. 
conica White, G. esnehensis Nakkady, G. gansseri Bolli, G. lapparenti lapparenti 
Brotzen, G. lapparenti tricarinata (Quereau), G. mayaroensis Bolli, G. intermedia 
Bolli, G. stuarti de Lapparent; Rugoglobigerina " cretacea Cushman " of Bermudez 
1952, R. esnehensis (Nakkady) ; Globigerina bulloides d'Orbigny, G. linaperta Finlay, 
G. pseudotriloba White, G. subcretacea Lomnicki ; Globorotalia membranacea (Ehren- 
berg) , Truncorotalia colligera (Schwager), T. crassata aequa (Cushman & Renz), 
T. esnaensis (Le Roy), T. simulatilis (Schwager), T. spinulosa (Cushman), T. velasco- 
ensis (Cushman), and T. wilcoxensis (Cushman & Ponton). 

Examination of their figures and very brief descriptions showed that : 

1. G. aegyptiaca Nakkady is an entirely single-keeled form which should be 

assigned to Globotruncana stuarti parva Gaudolfi. 

2. G. caliciformis (de Lapparent) (not Vogler), G. intermedia Bolli, G. stuarti (de 

Lapparent) and G. esnehensis Nakkady are all the same species and should be 
assigned to Globotruncana esnehensis Nakkady & Osman. 

3. G. gansseri Bolli, G. lapparenti tricarinata (Quereau), R. esnehensis (Nakkady), 

G. cretacea Lomnicki, G. membranacea (Ehrenberg), T. esnaensis (Le Roy) 
and T. spinulosa (Cushman) are doubtful forms. 

4. G. lapparenti lapparenti Brotzen probably belongs to Abathomphalus mayar- 

oensis (Bolli) as does G. mayaroensis Bolli. 

5. Rugoglobigerina " cretacea Cushman " of Bermudez, is possibly Globorotalia 

quadrata (White). 

6. Globigerina bulloides d'Orbigny is possibly Globorotalia pseudobulloides (Plum- 

mer), and both their G. linaperta Finlay, and G. pseudotriloba White probab- 
ly belong to G. triloculinoides Plummer. 

7. T. colligera (Schwager) probably belongs to Globorotalia angulata abundo- 

camerata Bolli. Schwager's form was recorded from younger strata, and 
the holotype of this species needs to be redrawn and redescribed as mentioned 
above. 

8. T. crassata aequa (Cushman & Renz) and T. wilcoxensis (Cushman & Ponton) 

probably belong to Globorotalia aragonensis Nuttall. 



58 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

9. T. esnaensis (Le Roy) probably belongs to Globorotalia whitei Wiess. 
10. Both their T. simulatilis (Schwager) and T. spinulosa (Cushman) probably 
belong to Globorotalia bollii sp. nov., and their T. velascoensis (Cushman) is 
probably Globorotalia angulata angnlata (White) or a transitional form 
between it and G. angulata abundocamerata Bolli. 

Said (i960) recorded the occurrence of three species of Globigerina , nine species of 
Globorotalia, and two species of Hastigerina in the shale and limestone succession of 
the Gebel Gurnah section, Luxor, which he regarded as Landenian-Ypresian in 
age. Again, practically all the species were misidentified and thus the stratigraphy 
was not correctly interpreted. Analysis of his description and figures showed that : 

1. Globigerina eocaena Giimbel probably belongs to Globigerina turgida Finlay. 

2. Globigerina inaequispira Subbotina probably belongs to Globigerina pseudo- 

eocaena Subbotina. 

3. Globigerina triloculinoides Plummer does not belong to this species, but may 

be one of its descendants. 

4. Globorotalia conicotruncata Subbotina is a doubtful form ; Subbotina's 

species is a junior synonym of Globorotalia angulata (White), while his 
figures are different. 

5. Globorotalia imitata Subbotina is a doubtful form ; it is different from 

Subbotina's original description and figures, and from hypotypes of G. 
imitata recorded in the present work. 

6. Globorotalia interposita Subbotina probably belongs to Globigerina soldadoensis 

Bronnimann. 

7. Globorotalia pentacamerata (Subbotina) is probably Globigerina mckannai 

White. 

8. Globorotalia planoconica Subbotina is not a Globorotalia but may be referable 

to the genus Globanomalina [? Globanomalina eocenica (Berggren)] as are his 
Hastigerina aspera (Ehrenberg) and Hastigerina micra (Cole). Ehrenberg's 
original form most probably belongs to the genus Globigerinelloides, and is 
not recorded from strata younger than Upper Campanian. 

9. Globorotalia pseudotopilensis (Subbotina) is probably Globorotalia esnaensis 

(Le Roy). 

10. Globorotalia simulatilis (Schwager) is probably Globorotalia subbotinae Morozova. 

11. Globorotalia thebaica Said is a junior synonym of Globorotalia prolata Bolli. 

12. Globorotalia velascoensis (Cushman) is possibly Globorotalia formosa formosa 

Bolli. 

Said & Kerdany (1961) described the following planktonic Foraminifera from the 
Maestrichtian-Lower Eocene succession of the Ain Maqfi section, Farafra Oasis, 
Egypt : Globotruncana area (Cushman), G. cretacea Cushman, G. esnehensis Nakkady, 
G. gansseri Bolli, G. rosetta (Carsey) ; Rugoglobigerina sp. cf. R. jerseyensis Olsson, 
R. reicheli pustulata Bronnimann ; Globigerina eocaena Giimbel, G. sp. cf. G. quadrata 
White, G. triloculinoides Plummer ; Globorotalia angulata abundocamerata Bolli, 
G. colligera (Schwager), G. convexa Subbotina, G. esnaensis (Le Roy), G. imitata 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 59 

Subbotina, G. pentacamerata Subbotina, G. pseudomenardii Bolli, G. pseudoscitula 
Glaessner, G. simulatilis (Sch wager), G. triplex (Subbotina), G. varianta (Subbotina), 
and G. velascoensis (Cushman). 

Analysis of their descriptions and figures showed that : 

1. G. area (Cushman) is probably Globotruneana gagnebini Tilev. 

2. G. gansseri Bolli is possibly Globotruneana rosetta rosetta (Carsey). 

3. G. rosetta (Carsey) is Globotrunacna stuarti stuarti (de Lapparent). 

4. G. eocaena Giimbel is apparently Globigerina turgida Finlay. 

5. G. convexa Subbotina is most probably Globorotalia angulata abundocamerata 

Bolli, while the figure described by them under the latter name is a doubtful 
form which is completely different from Bolli's original description and 
figures. 

6. G. pentacamerata Subbotina is Globigerina mckannai White. 

7. G. simulatilis (Schwager) probably belongs to Globorotalia occlusa Loeblich & 

Tappan. 

8. G. triplex (Subbotina) is probably Globorotalia loeblichi sp. nov. 

9. G. varianta (Subbotina) is possibly Globorotalia pseudobulloides (Plummer) 

while their G. valescoensis (Cushman) should be assigned to Globorotalia 
velascoensis velascoensis (Cushman). 
10. Rugoglobigerina reicheli pustulatais probably Rugoglobigerina rugosa (Plummer), 
while their R. sp. cf. R. jerseyensis Olsson, their G. cretacea Cushman, 
Globorotalia imitata Subbotina, G. pseudoscitula Glaessner, G. colligera 
Schwager, and Globigerina triloculinoides Plummer, are doubtful forms. 

In the present study, the rich planktonic foraminiferal fauna of the Upper Creta- 
ceous-Lower Tertiary sections provided the only means for precise zonation and 
inter-regional correlation. The short ranges of most species and their wide geo- 
graphical distribution points to their great stratigraphical value. However, as is 
indicated above, previous misidentifications, misinterpretations of stratigraphical 
ranges, over-brief specific descriptions, crude figures, the abundance of synonyms 
and homonyms, and the divergent views held by authors on various important 
taxonomic problems have all helped to mask the value of many species of planktonic 
Foraminifera in stratigraphical zonation and world correlation, and have filled the 
literature with an overwhelming amount of confused data. 

Although studies aimed at clarifying the identity and establishing the true 
stratigraphical ranges of various planktonic species have already been made by 
Cita (1948), Tilev (1951, 1952), Bolli (1951, i957«, b), Bolli, Loeblich & Tappan 
(1957), Subbotina (1953), Gandolfi (1955), Bronnimann & Brown (1956), Loeblich 
& Tappan (1957a), Bolli & Cita (1960&), Berggren (1960a, 1962), Pessagno (i960, 
1962), and Barr (1962), many problems were left unsolved and a new critical study 
was badly needed. Thus, this part of the work is mainly devoted to a study of the 
most important members of the recorded planktonic Foraminifera. Each species is 
treated in detail. Full synonymies with figures and descriptions, to the end of 
August, 1963, have been compiled (El-Naggar 1963), but, with a few exceptions, only 
the correct identifications are listed here. References without figures and descrip- 



60 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

tions are also discussed whenever necessary and the confusion surrounding the species 
is explained in detail wherever possible. 

Species of Globotruncana, Globorotalia and Globigerina are described and figured in 
detail except for a few that are very rare. Species of Abathomphalus, Rugoglobi- 
gerina, Trinitella and Hedbergella are only listed and will be dealt with in detail in a 
future publication, together with other planktonic Foraminifera such as Globigerinel- 
loides, Pseudotextularia, Pseudoguembelina, Guembelina, Planoglobulina, Racemig- 
uembelina and Heterohelix. Consideration of the ranges of these planktonic Foramin- 
ifera has led to the recognition of seven faunal zones and four subzones ; in addition, 
three other zones, which are either devoid of planktonic Foraminifera, or contain rare 
indeterminable forms, have also been recognised. (Text-figs 5 and 6). These zones 
and subzones are correlated with the corresponding macrofossil zones and subzones 
(Text-fig. 5), and with various planktonic foraminiferal zones in other parts of the 
world (Text-fig. 6), they are briefly discussed below and are from the base upwards, as 
follows : 

1. A non-fossiliferous zone. 

2. A zone with rare indeterminable planktonic Foraminifera. 

3. The Globotruncana fornicata Zone. 

4. The Globotruncana gansseri Zone. 

5. The Globotruncana esnehensis Zone. 

a/V^A^^A^o^^^A/^A^^A^\A^^/V^A^^A•^/V^A/ DisCOnformity <\M/WVWWV\M/VW 

6. The Globorotalia compressa/ Globigerina daubjergensis Zone. 

7. The Globorotalia angulata Zone. 

a. The Globorotalia uncinata Subzone. 

b. The Globorotalia pusilla Subzone. 

8. The Globorotalia velascoensis Zone. 

a. The Globorotalia pseudomenardii Subzone. 

b. The Globorotalia aequa / Globorotalia esnaensis Subzone. 

9. The Globorotalia wilcoxensis Zone. 

10. A zone with indeterminable planktonic Foraminifera. 

1. A NON-FOSSILIFEROUS ZONE. 

This zone coincides with the Nubia sandstone and variegated shale formation 
which is mostly devoid of fossils except for rare plant and vertebrate remains. 
Several samples were washed for foraminiferal investigation, but no Foraminifera 
were observed. 

2. A Zone with rare indeterminable planktonic Foraminifera. 

This zone coincides with the Sibaiya phosphate formation which contains extreme- 
ly minute forms of Foraminifera, that could only be seen in thin section and thus 
could not be identified with certainty. 

3. The Globotruncana fornicata Zone. 

This represents the lowest recognized planktonic foraminiferal zone in the succes- 



AGE 


PLANKTON IC FORAMINI FERAL ZONATIONS 




/ 


<> 

& 


/ 


PRESENT STUDY 
MLE VALLEY, EGYPT 


SUBBOTINA iifu.ifMi 
THE CAUCASUS. USSR. 


DALBIEZ linn 
TUNISIA 


BOLLI "«'„. h im»,i 
TRINIDAD 


LOEBLICH aTAPPANi.« Vh i 

Gulf ond Atfanlic Cooslal Ftans, 

U.SA 


OLSSON f i«oi 
New Jersey Coaslal Ptom, 
USA 


Tompico Embaymenl, 
MEXICO 


PESSAGNOiiw.wni 
PUERTO RICO 


BOLLI 8 OTA i.«o.. t i 
Poderno d'Addo Seclion 
ITALY 


LEONOV 8 ALIMARINA ( i»u 
The Caucasus 
USSR. 


> 

DC 

< 

h- 

rr 

u 
h- 


Ixl 

z 

LU 




LU 


j.ui.7 

I* 




Globorololia 
wilco»ensis 


b a c 
(Zone of 

compressec 
globarolaliidsi 


\z::~ 




Globorotolia 










Gtoborolola 


G. praenorfanensis 


LlI 

z 

LU 
<_> 
O 
LU 

_1 
< 
CL 


$ 

'-'-'::. 




GloborofaNo 


Gttadafro 

GloboroloJia/ 
esnoenss 


b 

G crossolo/ 

A intermedia 
subzone 


Giobomtotia 


Goborolo&o veJoscoensis 


Gioborolofci 
velcascoensis 


G cortcolruncala' 
Glodjrksionensis 


G subsphoerico 

- --i ™ - ■ 
Gfadjikis loners: 


Dseodamenordii 


pseudomenorda 


1 ve lascoe n 5 is /acuta / 




Gi.iK,-,',-.icjo velascoensis. 
Crjlc-r, -jd<a acuta/ 
'; c ;■:• i>3 spiralis 


Globorolalio pseudomeryydi 


pseudomenardn 


lu£ a 

- V 




G.'oborotoJa 
ongulolo- 


Globorotolia 
pusilla 


( Zone of 

globorotolods 
? 


G n ccr sfans 
subzone 


Globorolalio 


pseudobulJoides 


Globorotolia 


1 


Globorolalia 


pusilla pusila 


G. inconstons 
/G onguWa 


G angulalo 


Globorolato 
unonotO 


G/oborotolia 
unanaia 


Globorolalia 
uncmalo 


sutaone 


-si 




Qoborofaio compresso/ 


sujjjone. 


GiotxyoWio trirvdaden%is 


compre ss o/daubj e rge ns i s 


Globorolalio compresso/ 
Globigehnoides doutDjergensis 


Globigerincides 
doubiergensis 
Subzone 


Globoroloto fnndodenss 
/Globrgenna doubjerganss 


G pseudobulioides/ 
G. daubjerge fists 






Rzehakma 
epigona 


? 


? 




UJ 



< 

t- 

LlI 

cc 



to 

ID 
O 
LU 
O 

U 

(£ 
UJ 
D- 
Q. 

3 


2 
<C 
h- 

X 


J" 

< 

2 


i 


GlobolruKOno 




Gfobofrunccno 


Abaihomptwlus 




Rugogfobgermo 

jerseyenss/ 

Hedbergello 

monmoulhensis 


Abothomphdus 
mayaroer>S»S 


Globofruncana 
assemblage 


Abolrtomphojus 
mayoroensis 


Abolhompholis 
mayoroensis 




5 in 
1 


Qotxtfruncorw 

gonsseri 


Globolruncorto 
gonsseri 






Gtobotrunc ana 
gonsseri 




Z 


Globotruncono 
fomicofa 






Globolnjncono 


Globolfunccno 
Icpporenli 










Globolruncona 
forme alo/ 
lapparerti/ 


Rugolruncaoa 







Corr.:I;iti...n oi Hi-.- I'lanktnnii. R.rnmiml.T.il Zur 



,f the Esna-Idtu Rej 



e Valley, with the com^i'Minlmi: /ones in other par 




E, 



FIG. 7 



I 



s c 



■ ESNA-IDFU REGION. 

' CORRELATION CHART 

OF THE 

SECTIONS STUDIED. 



isc 



E LOWER EOCENE. 

D PALEOCENE. 

•"~- DIsconformity -~ v 

C MAESTRICHTIAN 

B OPPER CftMPANIAN 

A CAMPANIAN and ? 
PRE- CAMPANIAN. 

_, Location and number 
of samples studied 



-.-;*; 






SEtl EL- BAVOUMI 


GEBEl KOM-MIR 


CEBEl EL-SHARAWNA 


GEBEL EL- KILABIYA 


WAD EL-SHARAWNA 


CEBEL OWAINA 


ABOO SABOUN 


6E0EL A 314 


SECTION 


EL-BAHARV SECTION 


SECTION 


SECTION 


SECTION 


SECTION 


SECTION 


SECTION 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 61 

sion studied. It is characterized by the flood of the various subspecies of the 
Globotruncana fornicata group which is taken as the index species for the zone. 

The top part of the G. fornicata Zone is marked by the diappearance of G. fornicata 
fornicata, G. fornicata mananrensis, G. fornicata globulocamerata, G. contusa scutilla, 
G. contusa witwickae, G. mariai and G. tricarinata tricarinata, as well as by the first 
appearance of G. gansseri gansseri, G. ganserri subganserri, G. ganserri dicarinata, 
G. lugeoni, G. aegyptiaca duwi, G. conica, G. contusa contusa, G. contusa patelliformis, 
G. esnehensis, G. rosetta pettersi, G. sharawnaensis, G. stuarti parva, G. subcircumnodi- 
fer, G. sp. Rugoglobigerina glaessneri, R. macrocephala, R. pennyi, R. pustulata, and 
Trinitella scotti. 

It is also characterized by the presence of G. adamsi, G. aegyptiaca aegyptiaca, 
G. area, G. cf. convexa, G. fareedi, G. fundiconulosa, G. gagnebini, G. cf gagnebini, 
G. leupoldi, G. mariei, G. orientalis, G. rosetta rosetta, G. stuarti stuarti, G. stuarti 
stuartiformis , G. stuarti subspinosa, G. tricarinata columbiana, G. ventricosa, G. 
havanensis, Rugoglobigerina loetterli, R. rugosa, Hedbergella hessi compressiformis, 
H. hessi hessi, H. mattsoni, H. monmouthensis, and H. petaloidea. 

The G. fornicata Zone characterizes the " lower Sharawna shale member " and 
coincides with the Terebratulina gracilis Subzone of the macrofossil classification. 
Both its planktonic foraminiferal and macrofossil content as well as its stratigraphi- 
cal position (conformably overlying the Upper Campanian Lopha villei Zone) suggest 
a Lower Maestrichtian age as summarized above (see pp. 46-49). 

4. The Globotruncana gansseri Zone. 

This represents the second planktonic foraminiferal zone from the base of the 
succession upwards. It coincides with both the " Middle Sharawna marl member " 
and the lower part of the overlying " Upper Sharawna shale member ". It is charac- 
terized by the first appearance and the flood of the various subspecies of the G. gans- 
seri group, which is taken as the index species for the zone. Its base is marked by the 
top of the underlying G. fornicata Zone, and its top by the diappearance of G. area, 
G. bahijae, G. conica and G. sp. as well as by the great reduction in the number of 
individuals of the G. gansseri group and the flooding of G. esnehensis, and by the 
first appearance of R. rotundata. 

It is also characterized by the presence of Globotruncana aegyptiaca aegyptiaca, 
G. arabica, G. area, G. bahijae, G. cf. convexa, G. fareedi, G. fundiconulosa, G. gagnebini, 
G. gansseri gandolfii, G. leupoldi, G. mariei, G. orientalis, G. rosetta rosetta, G. 
stuarti stuarti, G. stuarti stuartiformis, G. stuarti subspinosa, G. youssefi, G. 
havanensis, Abathomphalus intermedia, Hedbergella hessi compressiformis, H. hessi 
hessi, H. monmouthensis, H. petaloidea, Rugoglobigerina glaessneri, R. loetterli, R. 
macrocephala, R. pennyi, R. pustulata, R. rugosa, and Trinitella scotti, as well as by the 
rare occurrence of the following forms at its base : G. adamsi, G. fornicata ackermanni, 
G. fornicata cesarensis, G. cf. gagnebini, G. tricarinata colombiana, G. ventricosa and 
Hedbergella mattsoni. 



62 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

The G. gansseri Zone characterizes the Middle Sharawna marl member as well as 
the lower part of the Upper Sharawna shale member, and coincides with the Pecten 
(Chlamys) mayereymari Sub-zone of the macro-fossil classification. Both its 
planktonic foraminiferal and macrofossil content suggest a Middle Maestrichtian age 
as indicated above (see pp. 47-49). 

5. The Globotruncana esnehensis Zone. 

This represents the third planktonic foraminiferal zone from the base of the 
succession upwards, and characterizes the topmost part of the Cretaceous rocks in the 
Esna-Idfu region. It is distinguished by the flood of Globotruncana esnehensis 
Nakkady & Osman which is taken as the index fossil of the zone. Its upper part is 
marked by a distinct break and by a well developed conglomerate which separates 
it from the overlying basal Tertiary. At this break the genera Globotruncana, 
Rugoglobigerina, Abathomphalus, Trinitella, Hedbergella, Globigerinelloides, Heter- 
helix and Pseudotextularia ; all ammonites and mosasaurs, as well as a great number of 
characteristic Upper Cretaceous species belonging to other groups, disappear 
completely and abruptly. 

The lower limit of the G. esnehensis Zone is marked by the flood of Globotruncana 
esnehensis and by a great reduction in the number of individuals of the G. gansseri 
Zone which all die out completely in its lower part, except G. gansseri gandolfii 
which continues to the disconformity. The lower limit of this zone is also marked 
by the disappearance of G. area, G. bahijae, G, conica, and G. sp. and by the first 
appearance of R. rotundata. 

The G. esnehensis Zone is generally characterized by the presence of Globotruncana 
aegyptiaca aegyptiaca, G. aegyptiaca duwi, G. arabica, G. contusa contusa, G. contusa 
patelliformis, G. cf. convexa, G. gagnebini, G. mariei, G. stuarti parva, G. subcircumno- 
difer, G. havanensis, Abathomphalus intermedia, A. mayaroensis, Hedbergella mon- 
mouthensis, H. petaloidea, Rugoglobigerina glaessneri, R. loetterli, R. pustulata, R. 
macrocephala, R. pennyi, R. rotundata and R. rugosa, as well as the rare occurrence 
oiG.fareedi, members of the G. gansseri group, G. leupoldi, G. lugeoni, G. orientalis, 
G. sharawnaensis, G. youssefi, and H. hessi hessi at its base. 

The G. esnehensis Zone is equivalent in part to the Abathomphalus mayaroensis 
Zone which is considered in various parts of the world to represent the uppermost 
Cretaceous, and is equated with the established uppermost Maestrichtian Belemni- 
tella casimirovensis Zone. However, although Abathomphalus mayaroensis was 
recorded in the G. esnehensis Zone, the latter zone could not be named after it, in 
spite of the advantage of this name in inter-regional correlation, as A. mayaroensis 
was only recorded as a rare form, while G. esnehensis was found to flood this part of 
the succession, wherever examined. 

6. The Globorotalia compressa/Globigerina daubjergensis Zone. 

This represents the fourth planktonic foraminiferal zone from the base of the 
succession upwards. It characterizes the lower part of the Lower Owaina shale mem- 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 63 

ber, which represents the lowermost Tertiary outcrop in the Esna-Idfu region, and 
the first known definite Danian strata in Egypt. The lower Owaina shale member is 
separated from the underlying Maestrichtian strata by a marked disconformity and 
a well developed conglomerate in which a mixture of reworked Maestrichtian 
macro fossils and typical Danain planktonic Foraminifera are recorded. 

The Globorotalia compressajGlobigerina daubjergensis Zone is characterized by the 
complete absence of the typical Upper Cretaceous Globotruncana, Abathomphalus , 
Rugoglobigerina, Trinitella, Hedbergella assemblage, and by the first appearance of the 
typical Tertiary, Globigerina /non-keeled Globorotalia assemblage. It is flooded with 
Globorotalia compressa (Plummer) and Globigerina daubjergensis Bronnimann which 
are considered as the index species for the zone. 

The base of this zone is marked by the disconformity and by the first appearance of 
the Globigerina /non-keeled Globorotalia assemblage. Its top is marked by the 
disappearance of Globorotalia compressa, Globorotalia kilabiyaensis, Globigerina 
daubjergensis and Globigerina arabica, and by the first appearance of Globorotalia 
angulata angulata, Globorotalia emilei and Globigerina inaequispira. Moreover, it 
is characterized by the abundance of the following Globorotalia species : G. pseudo- 
bulloides, G. trinidadensis, G. quadrata, G. perclara, G. kilabiyaensis, G. imitata, and 
the rare occurrence of G. ehrenbergi, G. faragi, G. tribulosa and G. uncinata uncinata 
in its upper part. It is also characterized by the abundance of the following Globi- 
gerina species: G. triloculinoides, G. triloculinoides parva, G. belli and by the rare 
occurrence of G. haynesi, G. kozlowskii and G. spiralis, at its top. 

The Globorotalia compressajGlobigerina daubjergensis Zone corresponds to the 
lower part of the macrofossil Caryosmilia granosa Zone. The planktonic Foramini- 
fera of this zone correlate it with the type Danian and thus prove a Danian age for its 
rich macrofossil content. However, the reduced thickness of this zone and the flood 
of Globorotalia compressa throughout it, show clearly that the strata it characterizes 
in the Esna-Idfu region, represent the Upper Danian only, the Lower and Middle 
Danian being missing (see Troelsen 1957 and Berggren 19606, 1962). 

7. The Globorotalia angulata Zone. 

This is the fifth planktonic foraminiferal zone from the base upwards, in the succes- 
sion studied. It coincides with the upper part of the lower Owaina shale member, 
and is characterized by the flood of Globorotalia angulata angulata (White) and its 
suspecies abundocamerata. Its base is marked by the first appearance of G. angulata 
angulata, G. emilei and by the disappearance of the typical Danian Globorotalia com- 
pressa, G. kilabiyaensis, Globigerina daubjergensis and G. arabica. 

The upper limit of this zone is drawn at the first appearance of Globorotalia 
velascoensis velascoensis which characterizes and distinguishes the overlying zone. 
This limit is also marked by the disappearance of Globorotalia ehrenbergi and G. 
uncinata carinata, and by the first appearance of Globorotalia acuta, G. apanthesma, 
G. cf. convexa, G. occlusa G. pseudomenardii , Globigerina alanwoodi and G. velasco- 
nesis. 



64 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFER A 

The zone is characterized by the abundance of the following Globorotalia species : 
G. angidata angulata, G. angidata abundocamerata, G. ehrenbergi, G. emilei, G. faragi, 
G. imitata, G. perclara, G. pseudobidloides, G. pusilla pusilla, G. pusilla laevigata, G. 
pusilla mediterranica, G. quadrata, G. tribulosa, G. uncinata uncinata, G. uncinata 
carinata and G. sp. It is also distinguished by the abundance of the following 
Globigerina species : G. haynesi, G. inaequispira, G. kozlowskii, G. spiralis, G. trilo- 
culinoides and G. triloculinoides parva. 

It is divided into two distinct subzones : a lower, Globorotalia uncinata Subzone 
and an upper, Globorotalia pusilla Subzone. The ranges of the various species 
characteristic of each subzone are shown on Text-figs. 12-16. 

The G. angidata Zone coincides with the upper part of the Carysomilia granosa 
Zone of the macrofossil classification. Its planktonic Foraminifera as well as its 
stratigraphical position (conformably overlying typical Upper Danian strata and 
underlying the G. velascoensis Zone of Upper Paleocene age) proves its Middle 
Paleocene age. However, as discussed earlier, the controversy over the chrono- 
logical and stratigraphical relationships of the various Paleocene stages and sub- 
stages, and the disagreement regarding their planktonic foraminiferal content, does 
not allow one to refer the G. angulata Zone to any known Paleocene stage or substage 
(see pp. 22-29, 59-61). 

8. The Globorotalia velascoensis Zone. 

This is the sixth planktonic foraminiferal zone from the base of the succession 
upwards. It coincides with the upper two members of the Owaina formation, the 
Middle Owaina chalk and the Upper Owaina shale members, and represents the Upper 
Paleocene of the sections studied. It is characterized by the flood of Globorotalia 
velascoensis velascoensis (Cushman) and its two subspecies parva and caucasica, 
which are here considered as the index species for the zone. 

The lower limit of the zone is marked by the first appearance of G. velascoensis 
velascoensis, and its upper limit by the complete disappearance of the last survivors 
of this species. The lower limit is also defined by the first appearance of the following 
Globorotalia species : G. acuta, G. apanthesma, G. cf. convexa, G. occlusa, G. pseudo- 
menardii, and the first appearance of both Globigerina velascoensis and alanwoodi. 

Its upper limit, besides being defined by the disappearance of G. velascoensis 
velascoensis, is also marked by the disappearance of the following Globorotalia 
species: G. acuta, G. angidata angulata, G. apanthesma, G. cf. convexa, G. nicoli, and 
by the disappearance of the following Globigerina species : G. velascoensis, G. tri- 
locidinoides, G. triloculinoides parva, G. inaequispira, G. haynesi, G. chascanona, 
G. bacuana, and by the first appearance of Globorotalia bollii. 

The G. velascoensis Zone is generally characterized by the abundance of the 
following Globorotalia species : G. velascoensis velascoensis, G. velascoensis parva, 
G. velascoensis caucasica, G. acuta, G. aequa, G. africana, G. angulata angidata, 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 65 

G. angidata abundocamerata, G. apanthesma, G. berggreni, G. cf. convexa, G. emilei, 
G. esnaensis, G. faragi, G. hispidicidaris, G. irrorata, G. woodi, G. nicoli, G. occlusa, 
G. perclara, G. pseudomenardii , G. pusilla mediterranica, G. sibaiyaensis, G. tribulosa, 
G. whitei, as well as the rare occurrence of G. imitata, G. pusilla pusilla, G. pusilla 
laevigata, G. quadrata, G. pseudobidloides and G. sp. at its base, and G. wilcoxensis, 
G. loeblichi, G. troelseni at its top. 

It is also characterized by the abundance of the following Globigerina species : 
G. aquiensis, G. bacuana, G. chascanona, G. haynesi, G. inaequispira, G. mckannai, 
G. nodosa, G. soldadoensis, G. spiralis, G. stonei, G. triloculinoides , G. triloculinoides 
parva, G. velascoensis and G. alanwoodi. 

The G. velascoensis Zone is clearly divisible, on the basis of its planktonic Fora- 
minifera, into two distinct subzones : a lower G. pseudomenardii Subzone and an 
upper G. aequajG. esnaensis Subzone. The lower subzone is distinguished by its 
index species, G. pseudomenardii Bolli, which does not range into the overlying 
subzone. The G. aequajG. esnaensis Subzone is also characterized by its index 
species which do not range into the underlying subzone, although rare forms of 
G. aequa may be recorded in the uppermost part of the underlying subzone. The 
distribution of the various planktonic foraminiferal species in each of these subzones 
is clearly shown on Text-figs. 12-16. 

The G. velascoensis Zone corresponds to the Ostrea hypoptera Zone and the lower 
part of the non-megafossiliferous zone in the macrofossil zonal scheme. On the 
basis of its planktonic foraminiferal content, and stratigraphical position, it is 
considered to represent the Upper Paleocene as stated above (see pp. 29-31, 49-51). 

9. The Globorotalia wilcoxensis Zone. 

This represents the last planktonic foraminiferal zone in the succession studied. 
It coincides with the Thebes calcareous shale member and probably includes at 
least part of the overlying Thebes limestone member, although the latter did not 
yield any identifiable planktonic Foraminifera. It is characterized by the abun- 
dance of Globorotalia wilcoxensis Cushman & Ponton, which is considered as the 
index species of this zone. 

The lower limit is marked by the disappearance of the following Globorotalia 
species : G. velascoensis velascoensis, G. acuta, G. angidata angulata, G. apanthesma, 
G. cf. convexa and G. nicoli as well as by the disappearance of the following Globi- 
gerina species : G. bacuana, G. chascanona, G. haynesi, G. inaequispira, G. triloculi- 
noides, G. triloculinoides parva, and G. velascoensis. It is also marked by the first 
appearance of G. bollii and the flood of G. wilcoxensis. The upper limit of the zone 
is not really known in the succession studied, as no younger zones have yet been 
recorded. 

The G. wilcoxensis Zone is characterized by a flood of G. wilcoxensis, which species, 
though appearing first as rare, scattered individuals in the uppermost part of the 
underlying zone, is nevertheless considered to be a good index fossil. The zone is also 



66 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

characterized by the abundance of the following Globorotalia species : G. troelseni, 
G. whitei, G. bollii, G. aequa, G. esnaensis and G. loeblichi, as well as by the abundance 
of both Globigerina stonei and Globigerina soldadoensis, and by the rare occurrence at 
its base of both Globigerina mckannai and Globigerina aquiensis. 

The G. wilcoxensis Zone corresponds to the upper part of the non-megafossiliferous 
zone and possibly the lower part of the overlying Lucina thebaica Zone, in the macro- 
fossil classification. On the basis of its planktonic Foraminifera, and stratigraphical 
position, it is considered to mark the dawn of the Eocene as discussed above (see 
pp. 31, 32, 51, 52). 

10. A ZONE WITH INDETERMINABLE PLANKTONIC FORAMINIFERA : 

This zone coincides with the Thebes limestone member, of which only the lowest 
ten metres crop out in the area studied. This hard, siliceous limestone bed which 
caps the succession is flooded with Nummulites, Operculina, Assilina, Discocyclina, 
etc., but has not yet yielded any identifiable planktonic Foraminifera, possibly 
because of its silicification. Several samples of this bed are now being processed for 
planktonic foraminiferal analysis using different techniques with the hope of recover- 
ing some identifiable forms. 

These planktonic foraminiferal zones clarify the stratigraphy of the Upper Creta- 
ceous-Lower Tertiary in Egypt, and their recognition in other parts of the world 
indicates that they can be successfully used for the zonation and world-wide correl- 
ation of strata of this age. 



V. SYSTEMATIC DESCRIPTIONS 

Order FORAMINIFERIDA 

Superfamily GLOBIGERINACEAE Carpenter, Parker & Jones 1862 

Family GLOBOTRUNCANIDAE Brotzen 1942 

This family is represented in the present study by the four genera, Globotruncana 
Cushman 1927, Rugoglobigerina Bronnimann 1952, Trinitella Bronnimann 1952, and 
Abathomphalus Bolli, Loeblich & Tappan 1957. Forty-five species and subspecies of 
Globotruncana, seven species of Rugoglobigerina, one species of Trinitella, and two 
species of Abathomphalus are recorded. Members of the genus Globotruncana are 
discussed in detail, while those of Rugoglobigerina, Trinitella and Abathomphalus are 
only listed and will be figured and described in a later publication. 

Genus ABATHOMPHALUS Bolli, Loeblich & Tappan 1957 
Type species : Globotruncana mayaroensis Bolli 195 1 

Abathomphalus intermedia (Bolli) 

195 1 Globotruncana intermedia Bolli : 197, pi. 35, figs. 7-9. 

1954 Globotruncana intermedia Bolli ; Ayala : 399, pi. 7, figs. 2a-c. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 67 

1955 Globotruncana intermedia intermedia (Bolli) Gandolfi : 48, pi. 3, figs. 8a-c. 

1956 Rugotruncana intermedia (Bolli) ; Bronnimann & Brown : 553, pi. 22, figs. 13-15. 
19566 Marginotrucana intermedia (Bolli) Hofker : 333, text-fig. 24. 

1956c Marginotruncana intermedia (Bolli) Hofker : 75, pi. 10, figs. j^a-c. 

1960a Globotruncana (Marginotruncana) intermedia Bolli ; Hofker : 225, text-fig. 2ia-c. 

1962 Praeglobotruncana (Praeglobotruncana) intermedia (Bolli) Berggren : 31, pi. 7, figs2a-c. 

Remarks. A few specimens of A. intermedia (Bolli) were recorded from both the 
Middle Maestrichtian G. gansseri Zone and the overlying Upper Maestrichtian 
G. esnehensis Zone. The species was recorded from the Maestrichtian of Trinidad 
(Bolli 1951, 1957a), of northeastern Colombia (Gandolfi 1955), of Cuba (Bronnimann 
& Brown 1956), of northwestern Germany and of Holland (Hofker 1956&, c) and of 
southern Scandinavia (Hofker 1960a ; Berggren 1962). 

Hypotype. P.45659. 

Horizon and locality. Hypotype from sample No. 16, Wadi El-Sharawna 
section. 



Abathomphalus mayaroensis (Bolli) 

1951 Globotruncana mayaroensis Bolli : 198, pi. 35, figs. 10-12. 

1953 Globotruncana mayaroensis Bolli : Subbotina ; 181, pi. 8, figs. za-c. 

1954 Globotruncana mayaroensis Bolli ; Ayala : 407, pi. 10, figs. la-c. 

? 1955 Globotruncana mayaroensis Bolli ; Gandolfi : 18, pi. 1, figs. 2a— c, text-fig. 4 (loa-b). 
1956 Globotruncana mayaroensis Bolli ; Knipscheer (in Ganss & Knipscheer) : 624, pi. 2, 

figs. 2a-c. 
1956 Rugotruncana mayaroensis (Bolli) Bronnimann & Brown ; 553-554, pi- 22, figs. 10-12. 

1956 Globotruncana mayaroensis Bolli ; Wicher : 136, pi. 13, figs. 7, 8. 

? 1956 Globotruncana mayaroensis Bolli : Said & Kenawy : 151, pi. 5, figs. 2$a-c. 

? 1956 Globotruncana lapparenti lapparenti Brotzen ; Said & Kenawy : 150, pi. 5, figs, i^a-c. 

1957 Globotruncana (Globotruncana) planata Edgell : 115, pi. 4, figs. 7-9. 

1957 Abathomphalus mayaroensis (Bolli) Bolli, Loeblich & Tappan : 43, pi. 11, figs. la—c. 
i960 Globotruncana mayaroensis Bolli ; Vinogradov : 313, pi. 5, figs. 26a-c. 
1962 Praeglobotruncana (Praeglobotruncana) mayaroensis (Bolli) Berggren : 32-36, pi. 7, 
figs. 3a-c. 

Remarks. Rare specimens of A. mayaroensis were recorded from the Upper 
Maestrichtian (G. esnehensis Zone). The species was also recorded from the Upper 
Maestrichtian of Trinidad (Bolli 1951, 1957a), of the Caucasus (Subbotina 1953), of 
northeastern Colombia (Gandolfi 1955), of Bavaria (Knipscheer 1956), of Cuba 
(Bronnimann & Brown 1956), of Austria (Wicher 1956), of northern Sinai, Egypt 
(Said & Kenawy 1956), of Australia (Edgell 1957), of Rumania (Vinogradov i960) 
and of southern Scandinavia (Berggren 1962). 

Hypotype. P.45660. 

Horizon and locality. Hypotype from sample No. 27, Wadi El-Sharawna 
section. 



68 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Genus GLOBOTRUNCANA Cushman 1927 
Type species: Pulvinulina area Cushman 1926 

19276 Globotruncana Cushman : 91 (Type species : Pulvinulina area Cushman 1926). 

1941 Rosalinella Marie : 237 (Type species : Rosalina linneiana d'Orbigny 1839). 

1956 Rugotruncana Bronnimann & Brosn : 546 (Type species Rugotruncana tilevi Bronnimann 

& Brown 1956). 
1956 Bucherina Bronnimann & Brown : 557 (Type species : Bucherina sandidgei Bronnimann 

& Brown, 1956). 
19566 Marginotruncana Hofker : 319 (Type species : Rosalina marginata Reuss 1845). 
1957a Globotruncanella Reiss : 135 (Type species : Globotruncana citae Bolli 1951 = G/o6o- 

truncana havanensis Voorwijk 1937). 
1957a Globotruncanita Reiss : 136 (Type species : Rosalina stuarti de Lapparent 1918). 
1957a Helvetoglobotruncana Reiss : 137 (Type species Globotruncana helvetica Bolli 1943). 

Emended Diagnosis: Test free, trochospirally coiled, with wide range of 
variation in size and shape, highly or moderately spiro-convex, biconvex plano- 
convex (umbilico-convex) , concavo-convex, or even parallel-sided ; dorsal side 
evolute, highly domed, convex, flat or even concave ; ventral side strongly umbilicate, 
moderately or strongly protruding, convex, flat or even concave ; equatorial periph- 
ery generally rounded or ovoid, sometimes polygonal, either entire or lobate, with 
single or double keel ; in double keeled forms, the two keels may be parallel or diver- 
gent, enclosing a narrow or wide peripheral band either at right angles or inclined to 
plane or coiling ; axial periphery subrounded, subacute, acute, subtruncate or 
truncate ; chambers generally arranged in 2-4 whorls, dextrally or sinistrally 
coiled ; all chambers seen on dorsal side, only those of last whorl seen on ventral side ; 
initial chambers generally globular, moderately or strongly inflated, later ones 
variable in shape, being ovoid truncate, lenticular acute, hemispherical, angular 
conical, angular truncate, angular rhomboid, etc. ; sutures on both sides curved or 
radial, raised or depressed, sometimes thickened, limbate and beaded ; umbilicus 
varies in shape and size, rounded, ovoid, stellate or polygonal, moderate or large, with 
or without an umbilical flange ; primary apertures interiomarginal, umbilical, but 
umbilicus covered by complex, imperforate cover-plate (tegilla) formed by fusion of 
apertural flaps extending from each chamber ; these tegilla pierced centrally and at 
their contacts with umbilical rim by a number of small accessory apertures along 
which primary apertures and umbilical region in general communicate with outside of 
test ; tegilla delicate with much thinner wall than rest of test and thus are rarely 
preserved ; but even when broken they leave remnants along umbilical margin ; 
wall calcareous perforate, except for imperforate keel or keels, peripheral band and 
tegilla ; surface smooth or roughened, papillose, nodose, or even spinose ; keel or 
keels, sutures and umbilical flange either thickened and limbate or strongly beaded ; 
dorsal keel of each chamber reflected on dorsal side of test as inter-cameral dorsal 
suture, dorsal keels of successive whorls constituting spiral suture ; ventral keel 
(when present) reflected on ventral side of test as inter-cameral ventral suture (either 
raised or depressed) ; it may continue along umbilical rim as raised, beaded, umbilical 
flange ; i.e. dorsal keel of nepionic stage continuing on following chambers as dorsal 
inter-cameral sutures, spiral suture and dorsal, marginal keel of last whorl, while 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 69 

ventral keel of nepionic stage (when present) continues as ventral inter-cameral 
suture, ventral marginal keel of last whorl and sometimes as umbilical flange. In 
single-keeled forms keel occasionally bifurcating on periphery to form dorsal as well 
as ventral inter-cameral suture, as in members of Globotruncana stuarti group. 

Discussion. Cushman (19276) described Globotruncana as a new genus, with 
Pulvinulina area Cushman 1926 as the type species. However, several species of 
this genus had been previously assigned to the genus Rosalina d'Orbigny 1826 
(e.g. R. marginata Reuss 1845, R. canaliculata Reuss 1854 an d R- stuarti de Lapparent 
1918). Thalmann (1933) considered Rosalina d'Orbigny to be a junior synonym of 
Discorbis Lamarck 1804, and thus substantiated the validity of the genus Globo- 
truncana. However, Brotzen (1948) stated that the type species of Discorbis 
Lamarck has not been determined for certain, and thus retained Rosalina d'Orbigny 
1826, and included in its synonymy : Discorbina Parker & Jones 1862, and Discorbis 
Lamarck of authors (part). Nevertheless, the apertural characters, the large 
umbilicus, the umbilical cover-plate, the keels and peripheral band, the shape of the 
chambers, etc., clearly distinguish Globotruncana from the above genera. 

The brief description of the apertural characters of the genus given by Cushman 
(19276) led to further complication. He merely stated that the aperture is on the 
ventral side, and later (1928) added "... aperture on the ventral side, often in 
well-preserved specimens with a thin plate-like structure over the umbilical area ..." 
However, Marie (1941) noticed that in morphologically similar forms, the apertures 
of the previous chambers remain open into the umbilicus. Thus he suggested 
including these forms in a separate genus which he named Rosalinella, with R. linnei 
(d'Orbigny) as type species. He included within his new genus : Rosalina d'Orbigny 
sensu de Lapparent 1918, Globotruncana Cushman 1927, Globorotalia Cushman 1927 
(part), as well as Rosalna d'Orbigny (part), Discorbina Parker & Jones (part), 
Globigerina d'Orbigny (part), Rotalia Lamarck (part) and Truncatulina d'Orbigny 
(part) of authors. Marie divided his genus Rosalinella on the basis of the peripheral 
character and general form of test into four subgenera which he did not name, but 
listed with examples as follows : 

I. Test with truncated periphery, bordered by two marginal keels. 

1. Subgenus typified by Rosalinella linnei (d'Orbigny). 

II. Test with acute periphery (single keeled) : 

(A) Contour regular 

[a] with large umbilicus. 

2. Subgenus typified by Rosalinella stuarti (de Lapparent). 

[b] with narrow umbilicus. 

3. Subgenus typified by Rosalinella velascoensis (Cushman). 

(B) Contour lobate 

4. Subgenus typified by Rosalinella appenninica (Renz). 

Thus, he included within his new genus, species typical of Globotruncana Cushman 
1927, of Globorotalia Cushman 1927, and of Rotalipora Brotzen 1942. Nevertheless, 
his description conforms well with that of Globotruncana as given by Cushman 



70 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

(1927, 1928) and emended by later authors. Thus Rosalinella Marie 1941 is consid- 
ered a junior synonym of Globotrnncana Cushman 1927. 

Reichel (1950) divided the genus Globotrnncana into four subgenera : Globotrnncana 
s.s., Rotalipora Brotzen, Thalmanninella Sigal and Ticinella Reichel. However, the 
apertural characters of the last three genera are different from those of Globotrnncana 
Cushman and they were therefore considered separately by Sigal (1952), Bolli, 
Loeblich & Tappan (1957) and Banner & Blow (1959). 

Gandolfi (1955) added a fifth subgenus to Reichel's classification, considering 
Rngoglobigerina Bronnimann as a subgenus of Globotrnncana Cushman. However, 
the absence of true keels and a peripheral band, the constant presence of well-develop- 
ed surface rugosity, and the fact that the two forms have not yet been proved to 
grade into one another, favour the consideration of Rngoglobigerina as a separate 
genus. 

Bronnimann & Brown (1956) described Rugotruncana as a new genus. They 
distinguished it from Globotrnncana by the fact that "... some or all later chambers 
exhibit fine discontinuous costellae or traces of costellae.", otherwise their descrip- 
tions of the two genera are identical. However, as previously mentioned by Bolli, 
Loeblich & Tappan (1957), surface ornamentation alone cannot be used as a generic 
character, and thus Rogotmncana should be considered a junior synonym of Globo- 
trnncana, although Banner & Blow (1959) considered it as a subgenus of the latter. 
Forms of Globotrnncana with a highly roughened surface are recorded, and variation 
of the surface rugosity within the same species population renders generic or sub- 
generic distinction impossible on this basis alone. Moreover, Bronnimann & Brown 
(1956) included Abathomphalus intermedia (Bolli) and A. mayaroensis (Bolli) within 
Rugotruncana, in spite of the difference in the apertural characters of the two genera. 
They also described Bucherina as a monotypic genus. They stated that it resembles 
Globotrnncana and Rugotruncana, but differs from both " in lacking an umbilical 
cover-plate and in exhibiting a shift in the axis of coiling ". They further stated 
that " short apertural flaps extend into the umbilicus but do not form a cover-plate". 
However, as mentioned above, the cover-plate is a very delicate structure which is 
rarely well-preserved, and the shift in the axis of coiling is not a generic character. 
The establishment of a new genus on such a weak basis cannot be accepted, and 
Bucherina Bronnimann & Brown is therefore considered a junior synonym of 
Globotrnncana Cushman. Again, these authors stated that Globigerina mckannai 
White may possibly belong to their new genus Bucherina. However, no apertural 
flaps were ever observed in G. mckannai, which is a true Globigerina, recorded only 
from the Upper Paleocene and Lower Eocene, where no globotruncanid-like forms 
are known. 

Hofker (1956) proposed Marginotruncana as a new genus. He distinguished it 
from Globotrnncana Cushman on the basis of a so-called strongly reduced primary 
aperture (protoforamen) in the latter, which is either completely lost or fused with 
a secondary aperture (deuteroforamen) in the former. He included within Margino- 
truncana, forms which actually belong to Globotrnncana Cushman, Abathomphalus 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 71 

Bolli, Loeblich & Tappan, Praeglobotruncana Bermudez and Rotalipora Brotzen, all 
of which differ markedly in their apertural characters. Moreover, a deuteroforamen, 
such as described by Hofker, had not been recorded in any of the forms he included 
in his Marginotruncana [e.g. G. marginata Reuss, G. stuarti (de Lapparent), G. contusa, 
(Cushman), etc.] which conform precisely with the description of the genus 
Globotruncana as given by Cushman (1927) and emended by later authors. Thus 
Marginotruncana Hofker is considered a junior synonym of Globotruncana Cushman. 

Reiss (1957) described Globotruncanita as a new genus and distinguished it from 
Globotruncana Cushman by its chamber form which is mostly polygonal in outline, 
its entirely single keel, and by its " distinctive apertural characters ". However, as 
admitted by Reiss, polygonal chambers are also recorded in Globotruncana Cushman. 
Again, the character of the keel, whether single or double, is of specific importance 
only within the genus Globotruncana, and cannot be used as a basis for splitting it into 
two distinct genera. Forms with a double keel are clearly shown in the present 
study to evolve into single-keeled forms (e.g. G. area -> G. leupoldi), all transitional 
stages being present. Finally, there is no fundamental difference in the apertural 
characters of the two genera as described by Reiss (1957) ; both have interiomarginal, 
umbilical primary apertures, and a cover-plate with accessory apertures. Thus 
Globotruncanita Reiss is considered a junior synonym of Globotruncana Cushman. 

Reiss also described Globotruncanella and Helvetoglobotruncana as two new genera 
and stated that Globotruncanella is closely related to Praeglobotruncana, although from 
his description, it is clearly seen that its apertural characters relate it to Globotruncana 
not to Praeglobotruncana. However, he distinguished Globotruncanella by its 
flatly trochospiral test and its undifferentiated keel which never shows any tendency 
to split into two keels (although his type species was observed in the present study 
and by Bronnimann & Brown (1956) to have an occasional ventral keel in the last 
chamber or two) . Otherwise, his description conforms well with that of Globotruncana 
Cushman. As the degree of flattening of the test and the double- or single-keeled 
nature of the peripheral band are characters of specific, rather than generic, import- 
ance, Globotruncanella Reiss is considered a junior synonym of Globotruncana 
Cushman. 

Similarly Helvetoglobotruncana was only distinguished by its rounded chambers 
and its subperipheral, monochotamic keel. Again, chamber shape and position of 
the keel cannot be accepted as generic characters. Forms of Globotruncana with 
globular chambers and a dorsally-shifted keel (e.g. Globotruncana arabica sp. nov.) 
are recorded in the present paper, and make the establishment of a new genus impos- 
sible on the basis of such minor morphological characters. Thus Helvetoglobotruncana 
Reiss is also considered a junior synonym of Globotruncana Cushman. 

Globotruncana Cushman 1927 is distinguished from Rugoglobigerina Bronnimann 
1952 by its keel or keels, imperforate peripheral band, less globular chambers and less 
rugose surface. Trinitella Bronnimann 1952 is transitional in character between 
Globotruncana and Rugoglobigerina. It can neither be included in the former 
because it lacks an entire keel and an imperforate peripheral band, nor in the latter 



72 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

because of its compressed last chambers and partially developed keel. Thus it is 
considered here separately, in spite of the fact that it is represented by only one 
species, until further study can reveal its true position. 

Globotrnncana is distinguished from Abathomphalus Bolli, Loeblich & Tappan 1957 
by its interiomarginal, umbilical aperture, which is extraumbilical in Abathomphalus ; 
by its generally large umbilicus, which is very much reduced in the latter genus ; 
by its complex tegilla which is single in Abathomphalus and by the fact that its 
accessory apertures are both infra- and intralaminal, not only infralaminal as in 
A bathomphalus. 

Globotruncana differs from Praeglobotruncana Bermudez 1952 in its umbilical 
aperture, umbilical cover-plate, and accessory apertures. It differs from both 
Globorotalia Cushman 1927 and Hedbergella Bronnimann & Brown 1958 in the above 
mentioned characters, as well as in the constant presence of a single or double keel. 

Remarks. The confusion surrounding most Globotruncana species has led the 
author to split the present forms as much as their morphology and stratigraphical 
ranges would allow. No splitting on the basis of minor morphological characters or 
of rare specimens has been attempted. This has helped to clarify the nature of each of 
the described forms, although further study (serial thin-sectioning and statistical 
analysis) may favour the merging of some of these morphologically similar forms. 

The present study has shown that the characters of specific value within the genus 
Globotruncana are as follows : 

1. The shape of the test (biconvex, planoconvex, concavoconvex, sprioconvex 

or parallel-sided) , which is a function of the relative shapes of both the dorsal 
and the ventral sides. Variation within the range of each shape has been 
observed, and is not of any taxonomic importance. 

2. The character of the keel, whether single or double, or transitional from one to 

the other ; and in the double-keeled forms the position of the two keels 
relative to each other and to the rest of the test (parallel or divergent, 
closely- or widely-spaced, equally- or unequally-developed, marginally 
situated or shifted either to the dorsal or the ventral side), which affect the 
size, shape and position of the peripheral band. 

3. The shape of the chambers on both the dorsal and ventral sides, the number of 

chambers in the test and in the last whorl, as well as the arrangement of the 
chambers. This affects the general shape of the test, the shape of its 
equatorial periphery (rounded, subrounded, polygonal, entire or lobate) ; 
the character of the sutures on both sides of test (straight or curved, raised 
or depressed), and the shape of the umbilicus. However, it should be 
noted that, other things being equal, variation in any of these characters 
separately is not of any taxonomic value. 

4. Character of the surface, whether smooth or rough, but not degree of rugosity. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 73 

Evolutionary Development of GLOBOTRUNCANA 
Although the evolutionary development of the genus Globotruncana has been 
discussed by several authors e.g. Reichel (1950), Hagn & Zeil (1954), Gandolfi (1955), 
Bronnimann & Brown (1956) and Cita (1963), its origin remains uncertain. However, 
the fact that the early part of the test in all representatives of the genus is reminiscent 
of Globigerina, led to the belief that the genus had probably evolved from a general- 
ized " Globigerina-like " stock. On the other hand, Globigerina, as fixed by the 
original designation of its type species (Globigerina bulloides d'Orbigny 1826) is 
known to have appeared first at the base of the Danian (i.e. after the disappearance 
of the genus Globotruncana), a fact previously recognized by various authors and 
confirmed by the present study. This throws doubt on the validity of the previous 
records of Globigerina species in Cretaceous and Upper Jurassic rocks. A restudy of 
these forms may prove them to be species of Hedbergella, Rugoglobigerina, Prae- 
globotruncana, Globotruncana, or other genera. Nevertheless, with the limits of our 
present knowledge, the genus Globotruncana may have originated in one of the 
following ways : 

1. Praeglobotruncana evolved into Globotruncana by the confinement of the 

aperture to an interiomarginal, umbilical position, and by the development 
of the umbilical cover-plate ; and Globotruncana in its turn evolved into 
Rugoglobigerina by the loss of the keel or keels and by the development of 
distinct surface rugosity. 

2. Hedbergella evolved in one direction into Praeglobotruncana which continued 

its evolution as mentioned above, and in another direction, into Globo- 
truncana by the confinement of the aperture to an interiomarginal, umbilical 
position, and by the development of both the cover-plate and the keel 
(or keels) : Globotruncana, in its turn evolved into Rugoglobigerina by the 
loss of the keel or keels and by the development of surface rugosity as 
mentioned above. 

3. Some of the so-called " Globigerina " species in the lower part of the Upper 

Cretaceous and even in the Lower Cretaceous may possibly belong to 
Rugoglobigerina (although the genus has, up till now, been recorded from the 
Campanian and Maestrichtian only), but the cover-plate is either broken or 
has been lost during the process of fossilization ; hence it can be suggested 
that a hypothetical " Rugoglobigerina " stock has probably evolved into 
Globotruncana by the flattening of the dorsal side and the development of 
keel or keels, although Gandolfi (1955) strongly emphasized the fact that 
most Globotruncana species had undergone a process of " globigerinization " 
to develop into Rugoglobogerina. 

However, nothing can be decided about the origin of Globotruncana until the 
earliest known globigerinid forms have been carefully examined and traced to the 
first known Globotruncana species, either directly or indirectly through Hedbergella, 
Praeglobotruncana, or Rugoglobigerina. 

Several evolutionary trends demonstrated by one or more lineages of the genus 
Globotruncana, were suggested by various authors, (e.g. Gandolfi 1955 ; Bronnimann 



74 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

& Brown 1956 and Cita 1963). However, the fact that the present study is mainly 
concerned with the Maestrichtian Globotruncana, makes it difficult to go into detail, 
although the phylogenetic development of each of the species discussed here, is 
dealt with in the remarks on each species, and the various lineages suggested in the 
present study are summarized in Text-fig. 10. The extension of such lineages 
downwards in older strata can only be substantiated by the study of continuous 
sections throughout the Upper Cretaceous. Nevertheless, the main evolutionary 
tendencies observed in the various Globotruncana species discussed in the present 
work can be briefly summarized as follows : 

(a) A tendency to reduce the ventral keel. 

(b) A tendency to reduce the size of test. 

(c) A tendency to increase the surface rugosity. 

Again, comparison with the known Globotruncana species in the Turonian, Coni- 
acian, Santonian and Campanian, shows that : 

1. The tendencies towards reduction of the ventral keel in double-keeled Globo- 

truncana, and towards increase in surface rugosity exist throughout the 
Upper Cretaceous. 

2. A tendency towards the gradual increase in the size of test is clearly documen- 

ted ; it reaches its maximum in the Lower Maestrichtian and is then 
reversed towards the Upper Maestrichtian. 

3. A tendency to increase the height of coiling in spiroconvex forms is observed 

from the Turonian throughout the Maestrichtian, and manifests itself in the 
flooding of Maestrichtian strata with representatives of the G. contusa 
group, G. conica, G. esnehensis, G. sharawnaensis, G. orientalis and G. 
fareedi. 

4. A tendency, upwards in the section, towards the modification of the shape of 

the chambers in the last one or two whorls from globular to ovoid, lenticular, 
petaloid, crescentic, trapezoidal, rectangular or even polygonal, although 
some of the last representatives still maintain the globular shape of the 
chambers. This modification of the chamber shape in the last one or two 
whorls affects the general shape of the test and also the shape and size of 
the umbilicus. 

5. There is a general increase in the number of individuals of each species and in 

the number of species and subspecies between the Turonian and the Maes- 
trichtian. This is accelerated in the uppermost Cretaceous, and results in 
the younger species having a much shorter range than the older ones. 

These tendencies, in general, agree well with previous observations by other 
authors, especially Bronnimann & Brown (1956), who also noted tendencies towards 
the "refinement of shell material " and towards an increase in the size of the aper- 
tural flaps at stratigraphically higher levels. Although exceptions have been noted 
to the above-mentioned trends, their existence is in no way invalidated. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 75 

Globotruncana adamsi sp. nov. 

(PL 8, figs. 2a-d.) 

Diagnosis. A Globotruncana distinguished by its small to medium-sized, dome- 
shaped, distinctly spiroconvex test ; its highly convex dorsal side and almost flat 
ventral one .; globigerine, strongly inflated early chambers and crescentic, distinctly 
elongated, gently plicate ones in the last whorl ; ovoid, slightly to moderately over- 
lapping chambers on ventral side ; two well-developed marginal keels, wide inclined 
peripheral band, and generally smooth to delicately papillose surface. 

Description. Test large, spiroconvex, roughly ovoid in outline ; dorsal side 
highly convex and moderately inflated ; ventral side almost flat ; equatorial peri- 
phery ovoid, slightly lobate, with two well-developed, heavily beaded marginal 
keels ; axial periphery truncate, bluntly subangular ; chambers on the dorsal side 
not all clear, but apparently 23 in number, arranged in 4 dextrally coiled whorls ; 
the initial chambers are small, globular, weakly inflated and increase very slowly in 
size ; they are followed by slightly larger, strongly inflated, globular chambers 
which increase moderately in size ; the last whorl is composed of 5 large chambers 
which increase rapidly in size, and are subglobular and strongly inflated in the early 
part, becoming crescentic, strongly elongated in the direction of coiling later ; the 
last chamber is weakly plicated ; on the ventral side there are 5 chambers which 
increase moderately in size, being subglobular in the early part, ovoid, slightly 
inflated and strongly overlapping later ; sutures on the dorsal side slightly curved, 
depressed in the early part, strongly curved, raised and distinctly beaded later ; on 
the ventral side the sutures are straight, radial, strongly depressed at first, curved 
forward, delicately beaded, slightly raised or running in sutural depressions later ; 
umbilicus roughly pentagonal in outline, wide, deep, bordered by slightly raised, 
delicately beaded umbilical ridges, and covered by complex tegilla of which rem- 
nants are still preserved ; primary apertures interiomarginal, umbilical ; tegilla, 
with accessory apertures, only poorly preserved ; wall calcareous, perforate except 
for the imperforate keels, peripheral band and tegilla ; surface delicately papillose 
especially on the ventral side ; the two marginal keels are well-developed and heavily 
beaded, the ventral one is slightly shifted towards the ventral side, and thus they 
enclose a relatively wide, slightly inclined peripheral band which becomes progres- 
sively narrower towards the last chamber. 

Dimensions of holotype. 

Maximum diameter = 0-46 mm. 

Minimum diameter = 0-36 mm. 

Thickness = 0-25 mm. (Across middle part of test) 

Main variation. 

1. Chambers 13-24, arranged in 3-4 whorls, generally dextrally coiled. 

2. Chambers in the last whorl 4-6. 

3. The two keels are either equally developed or the ventral one slightly weakens 

towards the last chamber. 



76 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Remarks. G. adamsi sp. nov. is morphologically similar to both G. fornicata 
fornicata Plummer and G. convexa Sandidge. It is distinguished from the former 
by its dome-shaped, distinctly spiroconvex test, and from the latter by its less truncate 
axial periphery, better developed marginal keels, and strongly elongated chambers 
in the last whorl which overlap more on the ventral side. 

Globotruncana adamsi sp. nov. is believed to have evolved from G. fornicata 
fornicata Plummer into G. contusa patelliformis Gandolfi, as suggested by the morpho- 
logical features and stratigraphical ranges of these three forms. It was probably 
confused in the past with G. fornicata Plummer (e.g. Cita 1948) and with G. calici- 
formis (de Lapparent) (e.g. Cita 1948, Bolli 1951 and Gandolfi 1955). However, 
these forms are not included in the synonymy of the present species as they lack the 
distinctly elongated chambers in the last whorl and were incompletely described by 
their respective authors. 

This species is named after Dr C. G. Adams of the British Museum (Natural 
History), London. 

Holotype. P.45511. 

Paratypes. P.45510. 

Horizon and locality. Holo- and paratypes from sample No. 4, Abou Saboun 
section. 

Stratigraphical range. The species is common to abundant throughout the 
Lower Maestrichtian G. fornicata Zone and the basal part of the Middle Maestrichtian 
G. gansseri Zone. It fades out gradually upwards in the section, and dies out comple- 
tely in the lower part of the latter zone. 

The forms described by Cita (1948) as G. fornicata Plummer and G. caliciformis 
(de Lapparent) which may possibly belong to the present species, were recorded from 
the Santonian-Maestrichtian and the Upper Campanian-Maestrichtian of Italy 
respectively. Similar forms described as G. caliciformis (de Lapparent) by Bolli 
(1951) and as G. caliciformis caliciformis (de Lapparent) by Gandolfi (1955) were 
recorded from the Maestrichtian of Trinidad and from what was described as Upper 
Santonian-Campanian of northeastern Colombia respectively. 



Globotruncana aegyptiaca aegyptiaca Nakkady 
(PI. 3, figs. 4a-d ; PI. 4, fig. 1) 

1950 Globotruncana aegyptiaca Nakkady : 690, pi. 90, figs. 20-22. 
? 1954 Globotruncana aegyptiaca Nakkady ; Nakkady & Osman : 75-76, pi. 20, figs, -zoa-c. 
1956 Rugotruncana skewesae Bronnimann & Brown : 550-551, pi. 23, figs. 4-6. 

Emended diagnosis. A Globotruncana distinguished by its medium to large- 
sized, distinctly quadrilobate test ; flat to weakly arched dorsal side and strongly 
protruding ventral one ; highly lobate equatorial periphery ; two strongly develop- 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 77 

ed marginal keels ; curved, raised, beaded dorsal sutures and radial incised ventral 
ones ; thick limbate umbilical flange ; very wide umbilicus, and generally rough 
surface. 

Description. Test large, quadrilobate in outline, planoconvex, umbilicoconvex, 
coiled in a very low trochospire ; dorsal side almost flat although the early chambers 
are very weakly raised above the circumambient last whorl ; ventral side strongly 
inflated and distinctly protruding ; equatorial periphery roughly quadrate, very 
distinctly lobate, with two well-developed, much thickened, beaded keels ; axial 
periphery truncate ; chambers on the dorsal side 17, arranged in 3 dextrally coiled 
whorls ; the initial ones are small, inflated, globigerine, increase slowly in size and are 
followed by typically crescentic chambers which increase moderately in size as 
added ; the last whorl is composed of 4, large, petaloid chambers which increase so 
slowly that they all appear to be equal in size ; on the ventral side the chambers are 4, 
large, roughly ovoid, distinctly protruding and increase very slowly in size ; sutures 
on the dorsal side are curved, raised, thickened and beaded ; on the ventral side they 
are short, radial and depressed ; umbilicus quadrate in outline, very wide, deep, 
surrounded by much thickened, limbate, delicately beaded ridges, and covered by 
complex tegilla of which remnants are still preserved ; primary apertures interio- 
marginal, umbilical ; tegilla with accessory apertures only poorly preserved ; 
wall calcareous, perforate except for the imperforate keels, peripheral band and 
tegilla ; surface distinctly papillose in the early part, smooth in the later part with 
the papillae extremely well developed on the early chambers of the last whorl 
especially on the ventral side ; the two marginal keels are almost parallel to each 
other and enclose a wide, depressed peripheral band. 

Dimensions of described specimen. 
Maximum diameter = 0-48 mm. 
Minimum diameter = 0.43 mm. 

Thickness = 0-23 mm. 

Main Variation. 

1. Chambers 15-19, arranged in 2^-3 whorls ; generally dextrally coiled but 

sinistral forms also occurr (out of 500 specimens picked at random, 4 coiled 
sinistrally) . 

2. Chambers in the last whorl 4-4I, very rarely 5, increasing very slowly in size. 

3. Chambers on the dorsal side flat, very weakly inflated, sometimes even 

depressed ; on the ventral side the chambers are always strongly inflated. 

4. Marginal keels, sutures and umbilical flange either heavily papillose or just 

thickened and limbate. 

5. The two keels are either equally developed or the ventral keel is sometimes 

reduced on the last chamber. 

6. Surface delicately papillose in early part, smooth in later part ; sometimes 

the papillae are so strongly developed that they give the surface a roughly 
nodose, or even spinose appearance. The beads on the marginal keel also 
taper out sometimes in the form of spine-like projections. 



78 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Remarks. Globotruncana aegyptiaca was first validly described by Nakkady 
(1950). He had, however, previously (1949) used the name without any description 
or figures. 

Nakkady (1950) gave only the dorsal view of the holotype, and the ventral and 
lateral views of two different paratypes. His choice of the paratype (1950, pi. 90, 
fig. 22) was rather unfortunate as it is a deformed specimen which does not reflect 
the ventral character of the holotype or the other paratypes. He described the 
umbilicus as wide, while on his fig. 22 it was shown to be rather narrow. He also 
stated that the dorsal side is always flat and that the periphery is " single keeled in 
most specimens but occasionally with a double keel ". However, examination of the 
holotype and paratypes of Nakkady (B.M.N.H.) Nos. P. 41773 and P. 41774, respec- 
tively) showed clearly that all the specimens are double keeled with a rare tendency 
towards the reduction of the ventral keel on the last chamber only (e.g. the holotype), 
and that the dorsal side is not always perfectly flat, but is sometimes weakly inflated, 
giving the test a very gently arched appearance. 

Nakkady (1950) described as varieties of G. aegyptiaca two distinct forms which he 
named G. aegyptiaca var. duwi and G. aegyptiaca var. /. Examination of the 
holotype of G. aegyptiaca var. duwi Nakkady (B.M.N.H. No. P. 41775) and 3 para- 
types, (P. 41776), and comparison with specimens in the present study, showed clearly 
that this variety is worthy of distinction as a separate subspecies, in contrast to 
Berggren's (1962) statement that it can probably be included in G. aegyptiaca. 
Thus the name is changed here to G. aegyptiaca aegyptiaca to distinguish it from 
G. aegyptiaca duwi. 

Globotruncana aegyptiaca var. /. Nakkady is a single keeled form which most 
probably belongs to the G. gansseri Bolli group, as previously mentioned by Berggren 
(1962) and substantiated by the examination of Nakkady 's holotype and one 
paratype (B.M.N.H. Nos. P.41777 and P.41778 respectively). 

Berggren (1962) considered G. gagnebini Tilev to be a junior synonym of G. 
aegyptiaca Nakkady. However, the study of a great number of individuals of both 
species has revealed that they are morphologically distinct. Globotruncana gagne- 
bini has a less lobulate, more tightly coiled, distinctly elongate test ; chambers 
which increase very rapidly in size, a much larger or much smaller last chamber and a 
greater number of chambers in the last whorl. 

Nakkady & Osman (1954) recorded G. aegyptiaca aegyptiaca from the Esna shales 
and chalk of both the Qabeliat and Sudr sections (southwestern Siani, Egypt), 
but their figures are not at all clear. 

Bronnimann & Brown (1956) described as Rugotruncana skewesae from the Middle 
Maestrichtian of Texas, a form which only differs from the holotype of G. aegyptiaca 
aegyptiaca Nakkady in having a distinctly developed spinose periphery, and faint, 
discontinuous costellae on the early chambers of the last whorl on the ventral side. 
Forms of G. aegyptiaca aegyptiaca with a distinctly spinose periphery and spinose 
early chambers on the ventral side were mentioned by Nakkady (1950), were 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 79 

observed in his paratypes (B.M.N.H. No. P. 41774), and are recorded in the present 
study. Bronnimann & Brown 1956 stated that " The distinctive feature of Rugo- 
truncana skewesae n. sp. is its very flat dorsal side. Globotruncana concavata (Brotzen) 
is the only globotruncanid known to us to have flatter dorsal side." Apart from the 
fact that G. concavata has a concave rather than a flat dorsal side, and that there 
are at least twenty known Globotruncana species and subspecies with a flat dorsal 
side, it is clear from their statement that these authors had completely overlooked 
G. aegyptiaca and its related forms which were described at least six years before 
their R. skewesae. Moreover, they described the last whorl in R. skewesae as having 

5 or 6 chambers, and included in its synonymy forms such as G. rosetta (Carsey) of 
Plummer (1927) and G. area (Cushman) of Jennings (1936) which are actually 
G. gagnebibi Tilev, thus indicating that they had also included within R. skewesae 
forms related to G. gagnebini. However, as the holotype of R. skewesae is identical 
with G. aegyptiaca aegyptiaca it is considered to be a junior synonym of the latter. 

Said & Kenawy (1956) described as G. aegyptiaca Nakkady, an entirely single- 
keeled form which is apparently G. stuarti parva Gandolfi, as mentioned under the 
latter species. 

The evolutionary history of G. aegyptiaca aegyptiaca is not clearly understood, 
although the morphological features of the species may suggest its evolution from 
G. ventricosa White through G. gagnebini Tilev and into G. aegyptiaca duwi Nakkady. 
However, it is not known whether G. gagnebini appears lower in the section than 
G. aegyptiaca aegyptiaca or not, as the two species were always confused with one 
another. In the sections studied, both species were found to occur together from 
the basal part of the Maestrichtian to the disconformity separating it from the 
overlying basal Tertiary. Thus it is not excluded that the two species might have 
evolved from two distinct but morphologically similar, forms. If so, the ancestral 
stock of G. aegyptiaca aegyptiaca may be sought in a form other than G. ventricosa 
White, which is more closely related to G. gagnebini Tilev. Globotruncana tricarinata 
colombiana Gandolfi is the only known, morphologically similar Globotruncana 
species which appears in older strata, and thus may possibly represent the ancestral 
stock from which G. aegyptiaca aegyptiaca has evolved. 

Hypotypes. P.45512-13. 

Horizon and locality. Figured specimens from Sample No. 16, Gebel 
Owaina section. 

Stratigraphical range : Nakkady (1950) described G. aegyptiaca aegyptiaca 
from the Maestrichtian Esna shale of the Abu Durba section, western Sinai, Egypt, 
and recorded it as rare to abundant in the chalk of W. Mellaha (Eastern Desert), 
the shale of W. Danili (western Sinai), and frequent to abundant in the chalk of 
G. Duwi (Eastern Desert), Egypt. The species was also recorded from the Camp- 
anian-Maestrichtian of both the Qabeliat and Sudr sections, Sinai, Egypt (Nakkady 

6 Osman 1954), and as R. skewesae from the Middle Maestrichtian of the Navarro 
group of Texas, (Bronnimann & Brown 1956). 



8o ll'PER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

In the Esna-Idfu region, G. aegyptiaca aegyptiaca floods the whole of the Maestrich- 
tian section, being extremely abundant in the G. fornicala and G. gansseri Zones, 
fading out gradually in the top part of the overlying G. esnehensis Zone, and dying 
out completely just below the disconformity separating the Maestrichtian from the 
overlying Paleocene. 



Globotruncana aegyptiaca duwi Nakkady 

(PL 3, figs. $a-c) 

1950 Globotruncana aegyptiaca Nakkady var. duwi Nakkady : 690, pi. 90, figs. 17-19. 

1954 Globotruncana aegyptiaca var. duwi Nakkady : Nakkady & Osman : 76, pi. 20, figs. 2ia-c. 

Emended diagnosis : A Globotruncana aegyptiaca with much smaller test 
and fewer chambers increasing very rapidly in size in last whorl ; ovoid to subtriangu- 
lar, slightly lobate periphery, and rougher surface. 

Description. Test medium-sized, roughly ovoid in outline, planoconvex, 
umbilicoconvex, coiled in a very low trochospire ; dorsal side almost flat, ventral side 
distinctly protruding ; equatorial periphery roughly ovoid, moderately lobate, 
with two well-developed, beaded keels ; axial periphery truncate ; chambers on 
the dorsal side, 11, arranged in 2 dextrally coiled whorls ; the initial chambers are 
small, globigerine, inflated, almost masked by the surface rugosity and increase 
slowly in size ; the last whorl is composed of 4 chambers which increase so rapidly 
in size that the last one constitutes about half of the test ; on the ventral side the 
chambers are 4, large, strongly inflated, distinctly protruding and increase very 
rapidly in size ; sutures on the dorsal side are curved, raised and beaded ; on the 
ventral side they are slightly curved forward, depressed and beaded ; umbilicus 
roughly quadrate in outline, relatively wide, deep, bordered by thick, raised, beaded 
ridges and covered by complex tegilla of which remnants are still preserved ; 
primary apertures interiomarginal, umbilical ; tegilla with accessory apertures only 
poorly preserved ; wall calcareous, perforate except for the imperforate keels, 
peripheral band and tegilla ; surface rough, distinctly papillose and spinose in the 
early part, with the roughness decreasing gradually towards the last chamber ; the 
two marginal keels are almost parallel to each other and enclose a wide, depressed, 
slightly inclined peripheral band. 

Dimensions of described specimen. 

Maximum diameter = 0-40 mm. 

Minimum diameter = 0-30 mm. 

Thickness = 0-22 mm. 

Remarks. Globotruncana aegyptiaca duwi was first described by Nakkady (1950) 
as a variety of G. aegyptiaca. However, the present study has shown that it is 
morphologically distinct from G. aegyptiaca aegyptiaca and that it appears in strati- 
graphically younger strata. Thus it is here raised to subspecific rank, although 
Berggren (1962) stated that it can probably be included in G. aegyptiaca s.s. Globo- 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 81 

truncana aegyptiaca duwi is believed to have evolved from G. aegyptiaca aegyptiaca as 
suggested by their morphological features and stratigraphical distribution. 

Gandolfi (1955 : 21, 22 ; text-fig. 5, 2a-c) included in his G. tricar inata colombiana, 
a form which possibly belongs to G. aegyptiaca duwi. 

Hypotype. P.45514. 

Horizon and locality. Figured specimen from sample No. 16, Gebel Owaina 
section. 

Stratigraphical range. Nakkady (1950) described G. aegyptiaca duwi from 
the Upper Cretaceous chalk of Gebel. Duwi section, Kossier area, Eastern Desert, 
Egypt, where it was described as rather frequent. It was also recorded from the 
Campanian-Maestrichtian of southern and western Sinai, Egypt (Nakkady & Osman 
1954) and from the Maestrichtian of Um El-Huetat section, Eastern Desert, Egypt 
(Ansary & Fakhr 1958). 

In the Esna-Idfu region, G. aegyptiaca dtiwi appears in the basal part of the 
G. gansseri Zone, and increases gradually in number upwards in the section becoming 
abundant in the upper part of this zone, and then fades out gradually, dying out 
completely at the top of the overlying G. esnehensis Zone. 



Globotruncana arabica sp. nov. 

(PL 6, figs. 3a-d ; PI. 11, fig. 4) 
Diagnosis. A Globotruncana with large, concavo-convex, strongly umbilico- 
convex test ; entirely single keel strongly shifted towards dorsal side ; chambers 
increasing slowly in size and distinctly inflated on ventral side ; very rough surface 
and large umbilicus. 

Description. Test large, subcircular, globular in outline, concavo-convex, 
distinctly umbilico-convex, coiled in a very low trochospire ; dorsal side shallowly 
concave, flat in the early part, slightly tilted inward in the last whorl ; ventral side 
strongly inflated and distinctly protruding ; equatorial periphery subcircular, 
globular and distinctly lobate, with a single, well developed, beaded keel which is 
strongly shifted towards the dorsal side ; axial periphery subrounded, very gently 
truncate ; chambers on the dorsal side about 17, arranged in 3 dextrally coiled 
whorls ; the initial chambers are small, globular, weakly inflated, almost masked by 
the surface rugosity and are followed by slightly larger, subglobular, weakly inflated 
ones ; the last whorl is composed of 5 large, subglobular, compressed chambers 
which increase slowly in size, are slightly elongated in the direction of coiling and 
strongly tilted inward towards the initial part ; on the ventral side the chambers are 
5, large, subglobular, strongly inflated, distinctly protruding, and enlarging so slowly 
that they all appear roughly equal in size ; sutures on the dorsal side are slightly 
curved, depressed in the early part, very short, slightly curved to almost straight in 
the later part, raised and beaded on the periphery, becoming depressed inward ; on 
the ventral side the sutures are straight, radial, and strongly depressed ; owing to the 



82 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

inward tilting of the dorsal surface of the last whorl the junction between the ventral 
and dorsal sutures can be seen from the the dorsal side ; umbilicus pentagonal in out- 
line, wide, deep, and covered by complex tegilla of which remnants are still preserved ; 
primary apertures interiomarginal, umbilical ; tegilla with accessory apertures only 
poorly preserved ; wall calcareous, perforate, except for the imperforate keel and 
tegilla ; surface rough, heavily papillose or even nodose, especially in the early part 
with the roughness decreasing gradually towards the last chamber ; the single 
marginal keel is distinctly beaded, with the beads slightly fading out on the penulti- 
mate and last chambers ; the keel of each chamber encircles its periphery and then 
disappears into the short, depressed, dorsal sutures ; the umbilicus is not bordered 
by a flange of any sort, although the large, scattered beads on the surface may 
simulate a beaded rim. 

Dimensions of holotype. 

Maximum diameter = 0-54 mm. 

Minimum diameter = 0-42 mm. 

Maximum thickness = 0-34 mm. (Thickness of last chamber) 

Minimum thickness = 0-23 mm. (Across middle part of test) 

Main variation. 

1. Chambers on the dorsal side 13-18, most commonly 15, arranged in 2^—3 

whorls, generally dextrally coiled. 

2. Chambers in the last whorl 4^—6, slowly to moderately increasing in size. 

Remarks : Globotruncana arabica sp. nov. is distinguished by its large, concavo- 
convex, strongly umbilico-convex, single keeled test, its large umbilicus and rough 
surface. The only known Globotruncana species with a concavo-convex, umbilico- 
convex test are : G. concavata (Brotzen) 1934, from the Campanian-Santonian of 
Palestine, G. repanda Bolli 1957, from the Campanian of Trinidad, and G. bahijae 
sp. nov. from the Maestrichtian of the Esna-Idfu region. The first species is 
distinguished from G. arabica by its closely spaced double keel, less concave dorsal 
side, chambers which increase more rapidly in size, and by its smooth surface. The 
second is differentiated by its smaller test, fewer number of chambers, double keel 
in the early part (which may be absent in the penultimate and last chambers), 
much smaller early part, and less rugose surface. The third is distinguished by its 
less protruding ventral side and its double keel. Globotruncana arabica sp. nov. 
is morphologically closely related to G. repanda Bolli. Small specimens of G. arabica 
resemble G. repanda, but differ in having an entirely single keel, and chambers 
which increase slowly in size. By reduction of the ventral keel and increase in the 
size of test, in the number of chambers and in the surface rugosity, G. repanda might 
possibly have evolved into G. arabica. Such tendencies are clearly recorded in 
G. repanda, but the latter species is known to die out completely in the Upper Cam- 
panian, while G. arabica is only recorded from the Middle and Upper Maestrichtian. 
Thus it is suggested that G. arabica either evolved from a yet undescribed form, 
transitional between it and G. repanda, or that the latter also occurs in the Lower 
Maestrichtian, but has not yet been found. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 83 

Globotruncana arabica sp. nov. is also morphologically related to G. lugeoni Tilev 
and G. youssefi sp. nov. which occur in association with it. It is distinguished from 
the former by its larger test, its strongly shifted keel towards the dorsal side, its 
shorter, less curved, depressed dorsal sutures and its much wider umbilicus. It 
differs from the latter by the fact that G. youssefi has an almost flat dorsal side, or 
even slightly raised initial part, longer, more curved, raised and beaded dorsal 
sutures and a truly marginal keel. 

Holotype. P. 45515. 

Paratypes. P. 45516. 

Horizon and locality. Holo- and paratypes from sample No. 22, W. El- 
Sharawna section. 

Stratigraphical range. The species appears for the first time in the upper 
part of the Middle Maestrichtian G. gansseri Zone. It increases in number upwards 
in the section until it floods the uppermost part of this zone and the basal part of the 
overlying G. esnehensis Zone before dying out completely in the middle part of the 
latter zone. 

Globotruncana area (Cushman) 

(PI. 1, figs, ia-2) 

1926a Pulvinulina area Cushman : 23, pi. 3, figs. la-c. 

1927a Globotruncana area (Cushman) Cushman : 91, pi. 19, figs. na-c. 

1937a Globotruncana area (Cushman) ; Glaessner : 36, pi. i, figs, ioa-c. 

1946 Globotruncana area (Cushman) ; Cushman (pars) : 150, pi. 62, figs. \a-c (non figs. $a-c). 

195 1 Globotruncana area (Cushman) ; Bandy : 509, pi. 75, figs. la-c. 

1951 Globotruncana area (Cushman) ; Noth : 77, pi. 8, figs, i^a-c. 

1951a Globotruncana area (Cushman) ; Nakkady (pars) : 56, pi. 1, figs. 4B-E, non fig. 4A. 

195 1 Globotruncana area (Cushman) ; Tilev : 57, text-figs. i8a-d, iga-d. (See also Tilev 

1952, where figures are repeated.) 
!953 Globotruncana area (Cushman) ; Hagn : 97, pi. 8, figs, na-c, text-figs. 20, 21. 
*953 Globotruncana area (Cushman) ; Subbotina : pp. 185-188, pi. g, figs. ia-5c, pi. io, 

figs. IO-5C. 
z 955 Globotruncana area area (Cushman) ; Gandolfi (pars) : 63, pi. 5, figs. 3a-c ; non figs. 

2a-c, 4a-c. 

1956 Globotruncana area (Cushman) ; Bronnimann & Brown : 539, pi. 23, figs. 10-12. 

1957 Globotruncana (Globotruncana) area (Cushman) ; Edgell (pars) : no, pi. 3, figs. 4-6 ; 
non pi. 1, figs. 10-12. 

1957 Globotruncana area (Cushman) ; Bolli, Loeblich & Tappan : 44, pi. n, figs. 6-nc. 

1958 Globotruncana area (Cushman) ; Bieda : 60, text-fig. 24. 

i960 Globotruncana area (Cushman) ; Vinogradov : 313, pi. 5, figs. 2ja-c. 
1962 Globotruncana area (Cushman) ; Barr : 567, pi. 69, figs. 8a-c. 

Emended diagnosis. A Globotruncana with large, robust, biconvex test ; 
great number of chambers per test and in last whorl ; two well-developed, much 
thickened beaded keels ; wide, inclined peripheral band ; curved, much thickened, 
raised, beaded sutures ; distinct, horseshoe-shaped ridge of beads outlining each 
chamber on ventral side ; wide umbilicus. 



84 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Description. (PI. i, figs. za-c). Test large, robust, unequally biconvex, coiled 
in a relatively high trochospire ; dorsal side convex, broadly arched, ventral side 
moderately inflated, slightly protruding ; equatorial periphery subcircular, moder- 
ately lobate ; axial periphery angular, slightly truncate, with two well-developed, 
strongly thickened marginal keels ; chambers on the dorsal side 22, arranged in 3^ 
dextrally coiled whorls ; the initial ones are small, inflated, globigerine, increase very 
slowly in size and are followed by typically crescentic chambers ; the last whorl is 
composed of 7 (6+1 abortive), large, typically crescentic chambers (except for the 
fourth and fifth) which increase slowly in size ; on the ventral side these chambers 
are subglobular to ovoid, moderately inflated, sharply outlined by distinctly thicken- 
ed horseshoe-shaped ridges ; sutures on the dorsal side curved, raised, thickened and 
beaded except on both sides of the antepenultimate chamber where they tend to be 
almost straight ; on the ventral side the sutures are short, thickened, raised, beaded 
and slightly curved forward ; umbilicus roughly hexagonal in outline, wide, deep, 
surrounded by raised ridges and covered by complex tegilla of which remnants are 
still preserved ; primary apertures interiomarginal, umbilical ; tegilla with accessory 
apertures only poorly preserved ; wall calcareous, perforate except for the imperfo- 
rate keels, peripheral band and tegilla ; surface smooth except for a few small, 
scattered papillae ; the two subparallel keels are well-developed, limbate and beaded, 
they enclose a relatively wide, depressed, inclined peripheral band except on the last 
chamber where the two keels become closer to each other ; the dorsal keel is more 
developed and strongly protruding while the ventral keel is slightly shifted towards 
the inner part of test. 

Dimensions of described specimen. 

Maximum diameter = 0-52 mm. 

Minimum diameter = 0-46 mm. 

Thickness = 0-27 mm. 

Main variation. 

1. Chambers on the dorsal side 18-24, arranged in 3-4 whorls, generally dextrally 

coiled. 

2. The last whorl is composed of 5-8 chambers, but 6-7 is most common. 

Remarks : Globotruncana area (Cushman) was first described by Cushman (1926) 
as Pulvinulina area n.sp. He later (1927) erected Globotruncana as a new genus, with 
Pulvinulina area Cushman 1926, as type species. 

Plummer (1931) described as G. area, double- and single-keeled forms which 
differ from Cushman's original description and figures. Bronnimann & Brown 
(1956 : 450) stated that " Her two-keeled forms are specimens of Git. cretacea 
Cushman which is an incipient Git. rosetta (Carsey). Her one-keeled forms are 
actually double-keeled, but the two keels are very close together ; they are well- 
developed specimens of Git. rosetta." 

Cushman (1932) described as G. area, a planoconvex, single-keeled form, and in 
1946 he presented the figures of the holotype and of this form as G. area. Cita (1948) 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 85 

interpreted Cushman's single-keeled form as G. rosetta (Carsey), while Bolli (1951) 
stated that it probably belongs to the Globotruncana stuarti group. Gandolfi (1955) 
made this form the basis of a new species which he named Globotruncana bollii, 
while Dalbiez (1955) considered it to belong to his subspecies G. elevata stuartiformis 
Dalbiez, [=G. stuarti stuartiformis Dalbiez]. 

Gandolfi (1955) described Globotruncana area caribica as a new subspecies of 
G. area (Cushman) and thus changed the latter's name to G. area area (Cushman) . 
However, G. area caribica appears to be a junior synonym of G. gagnebini Tilev 1951, 
thus the name G. area (Cushman) is here retained. Similarly, Said & Kerdany (1961) 
described as G. area (Cushman) from the Maestrichtian chalk of the Farafra Oasis, 
Egypt, a form which probably belongs to G. gagnebini Tilev. 

Globotruncana area (Cushman) is believed to have evolved from the G. linneiana 
(d'Orbigny) (=G. lapparenti Brotzen) stock as previously mentioned by Cita (1948), 
Bolli (1951), Bronnimann & Brown (1956) and Berggren (1962). On the other hand, 
G. area was itself found to show three main evolutionary tendencies which are as 
follows : 

1. A tendency towards the reduction of the ventral keel on the final chambers 

leading to G. leupoldi Bolli. 

2. A tendency towards the flattening of the ventral side and the reduction of the 

ventral keel leading to G. orientalis sp. no v. 

3. A tendency to reduce the size of test and the number of chambers in the last 

whorl leading to G. convexa Sandidge. (see PI. 1, figs. 3a-c.) 
The morphological characters and stratigraphical ranges of the five species 
(G. linneiana, G. arca,G. leupoldi, G. orientalis and G. convexa) support this hypothesis. 

Hypotypes. P.45517. 

Horizon and locality. Figured specimens PI. 1 figs. la-c, 2, from sample No. 4, 
Abou Saboun section, and figs. 3«-c, from sample No. 23, W. El-Sharawna section. 

Stratigraphical range : The species was first described from the upper part 
of the Papagallos shales (Mendez shale) of Mexico which was later considered to be of 
Maestrichtian age. 

Analysis of all previous records of G. area (Cushman) shows that it has a world-wide 
distribution, and that it occurs mainly in the Maestrichtian and the uppermost 
Campanian. However, owing to misidentification of the species and confusion with 
various other species, its true stratigraphical range has hitherto been obscured. 
Bronnimann & Brown (1956) stated that G. area appears to be restricted to Maestrich- 
tian strata and that all occurrences reported from pre-Maestrichtian strata are 
probably erroneous. They added that it is best developed in Upper Maestrichtian 
strata, and this was partially substantiated by Berggren (1962 : 51). However, 
G. area was recorded by Barr (1962) from the uppermost part of the Belemnitella 
mucronata Zone of the Isle of Wight, England, and from the Upper Campanian of the 
Paris Basin by the present author. 



86 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

In the Esna-Idfu region G. area occurs as an abundant form in the G. forncatai 
Zone and in the lower part of the overlying G. gansseri Zone. It fades out gradually 
in the upper part of the latter zone, and dies out completely before the overlying 
G. esnehensis Zone. 

Globotruncana bahijae sp. nov. 

(PI. 6, figs. 2a-d) 

Diagnosis. A Globotruncana with concavo-convex test, weakly developed 
double keel, wide peripheral band, rough surface and very wide umbilicus. 

Description. Test large, roughly ovoid in outline, concavo-convex, coiled in 
a very low trochospire ; dorsal side gently concave with the early whorls depressed 
and the last chambers slightly sloping towards the central part of test, ventral side 
inflated and moderately protruding ; equatorial periphery roughly ovoid, moderately 
lobate with two widely spaced, delicately beaded marginal keels which are slightly 
masked by the surface rugosity ; axial periphery subrounded, subtruncate ; chambers 
on the dorsal side 15, arranged in 2§ dextrally coiled whorls ; the initial chambers are 
small, weakly inflated, globigerine, and increase slowly in size ; they are followed by 
relatively large, subglobular, compressed chambers which increase slightly more 
rapidly in size ; the last whorl is composed of ^h large, crescentic, compressed 
chambers which are slightly tilted towards the central part and increase slowly in 
size ; on the ventral side the chambers are 5-3-, subglobular, slightly elongated in the 
direction of coiling, strongly inflated, moderately protruding, very loosely coiled and 
increase slowly in size ; sutures on the dorsal side slightly curved, depressed in the 
early part, strongly curved, raised and delicately beaded in the last whorl ; on the 
ventral side the sutures are straight, radial and strongly incised ; umbilicus hexago- 
nal in outline, very wide, relatively shallow, covered by complex tegilla ; primary 
apertures interiomarginal, umbilical ; tegilla, with accessory apertures, reasonably 
well-preserved ; wall calcareous, perforate except for the imperforate keels, peripheral 
band and tegilla ; surface rough, covered with large papillae which are slightly 
reduced towards the last chamber ; the two marginal keels are delicately beaded, the 
dorsal one is alwayswell-developed but the ventral is sometimes almost masked by the 
surface rugosity ; the two keels slightly diverge from each other and enclose an 
irregular, relatively wide peripheral band. 

Dimensions of holotype. 

Maximum diameter = 0-45 mm. 

Minimum diameter = 0-32 mm. 

Thickness = 0-20 mm. (of last chamber) 

Main variation 

1. Chambers on the dorsal side 13-18, arranged in 2^-3 whorls, usually dextrally 

coiled, but sinistral forms occasionally occur (of 67 specimens picked at 
random, 1 coiled sinistrally). 

2. Chambers in the last whorl 5-7 increasing slowly to moderately in size. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 87 

Remarks. Globotruncana bahijae sp. nov. is morphologically rather similar to each 
of the following Globotruncana species, all of which, except the last, appear in 
stratigraphically older strata : 



Globotruncana concavata (Brotzen). 

Globotruncana fundiconulosa Subbotina. 

Globotruncana (Rugoglobigerina) pennyi sunpennyi Gandolfi. 

Globotruncana repanda Bolli. 

Globotruncana arabica sp. nov. 



However, it is distinguished from G. concavata (Brotzen) by its more concave 
dorsal side and less protruding ventral one, widely spaced keels, chambers which 
increase less rapidly in size and rough surface. 

It differs from G. fundiconulosa Subbotina in its more concave dorsal side, less 
strongly developed marginal keels, chambers which increase more rapidly in size 
and radial depressed ventral sutures. 

It is more closely related to the form described by Gandolfi (1955) as G. (Rugo- 
globigerina) pennyi subpennyi, but differs from it in its concave dorsal side and less 
protruding ventral one and by its widely spaced marginal keels. It might possibly 
have evolved from the latter subspecies which appears to be a true Globotruncana 
(not a Rugoglobigerina), although Gandolfi's description does not allow a definite 
decision. 

Globotruncana bahijae sp. nov. is distinguished from both G. repanda Bolli and 
G. arabica sp. nov. by its compressed test, less protruding ventral side, greater 
number of chambers and widely spaced keels. 

Holotype. P.45518. 

Paratypes. P.45519. 

Horizon and locality. Holo- and paratypes from sample No. 18 W. El-Sharawna 
section. 

Stratigraphical range. The species appears for the first time in the middle 
part of the Middle Maestrichtian G. gansseri Zone. It increases in number upwards 
in the section to flood the upper part of the latter zone and then fades out gradually, 
disappearing completely before the overlying G. esnehensis Zone. 



Globotruncana conica White 
(PL 12, figs. 2a-d) 

19286 Globotruncana conica White : 285, pi. 38, figs. ja-c. 
? 1950 Globotruncana (Globotruncana) sp. aff. conica White ; Reichel : 614, text fig. yb. 
? 195 1 Globotruncana conica White ; Tilev : 67, figs. 22a-d. (See also Tilev 1952 where 
figures are repeated.) 

1956 Globotruncana conica White ; Said & Kenawy : 150, pi. 5, figs. i6a-c. 



88 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Emended diagnosis. A Globotruncana with large, broadly conical test ; 
almost circular slightly lobate equatorial periphery, and angular to subangular axial 
one ; entirely single keel ; broadly conical dorsal side and flat to slightly concave 
ventral one ; numerous chambers and whorls, and large number of chambers in 
last whorl ; globigerine initial chambers and subcircular to crescentic intermediate 
ones, which become roughly rectangular in last whorl ; raised, beaded, almost 
straight dorsal sutures, and curved, depressed ventral ones ; ovoid overlapping 
chambers on ventral side and wide deep umbilicus. 

Description. Test large, broadly conical ; dorsal side highly raised, with the 
various whorls arranged in the form of a cone with a rather sharp apex and a very 
broad base ; ventral side flat although the chambers are slightly inflated ; equatorial 
periphery almost circular, slightly lobate with a single, well-developed, beaded keel ; 
axial periphery subangular ; chambers on the dorsal side 24, arranged in 4 dextrally 
coiled whorls ; the initial chambers are very small, slightly inflated, globigerine and 
are followed by relatively larger chambers which are crescentic to semicircular and 
increase moderately in size ; the last whorl is composed of 6 large, roughly rectangular 
chambers which are elongated in the direction of coiling and increase slowly in size ; 
on the ventral side the chambers are 6, roughly ovoid to subcircular, slightly elonga- 
ted, moderately inflated and overlapping especially in the later part ; sutures on the 
dorsal side slightly curved in the early part, almost straight and angular later, 
distinctly raised, thickened and beaded ; on the ventral side the sutures are depressed, 
generally curved forward in the later part, tending to be nearly radial in the early 
part, beaded and running in sutural depressions formed by the slight inflation of the 
chambers ; umbilicus circular, relatively wide, deep, surrounded by slightly raised, 
beaded ridges and covered by complex tegilla of which remnants are still preserved ; 
primary apertures interiomarginal, umbilical ; tegilla with accessory apertures only 
poorly preserved ; wall calcareous, perforate except for the imperforate keel and 
tegilla ; surface smooth. 

Dimensions of described specimen. 
Maximum diameter = 0-51 mm. 
Minimum diameter = 0-48 mm. 

Thickness = 0-28 mm. 

Main variation. 

1. Chambers 21-24, arranged in 3-4 whorls generally dextrally coiled (all 

studied specimens coiled dextrally). 

2. Chambers in the last whorl 6-7, rarely 8. 

Remarks. Globotruncana conica was first described by White (1928), but his 
description was so short and incomplete that the species has often been misidentified, 
and its morphological characters and stratigraphical range much confused. The 
short description led most of the following authors to describe any Globotruncana 
species with a convex dorsal side and a flat ventral one as G. conica White. As a 
result, most of the existing figures are inadequate and most authors tend to speak of 
G. cf. conica White, rather than G. conica White. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 89 

Glaessner (1937a) and Keller (1946) described as G cf. conica White and G. conica 
White respectively, forms which possibly belong to G. contusa Cushman. The 
form described by Cushman & Renz (1947) as G- conica is doubtful, while that 
described by Cita (1948) can probably be assigned to G. orientalis sp. nov. Again, the 
form described by Bolli (1951) as G. conica White is probably G. stuarti stuarti 
(de Lapparent). 

Tilev (1951, 1952) described as G. conica White, a form with only 5f chambers in 
the last whorl, and distinctly outlined chambers on the ventral side. This form is 
questionably related to the present species. However, the fact that Tilev included 
in the synonymy of his G. conica, forms such as G. conica var. plicata White and G. 
linnei caliciformis (de Lapparent), which are probably synonymous with G. contusa 
contusa (Cushman) and G. contusa patelliformis Gandolfi respectively, throws doubt 
on the identification of his specimens. Tilev also described as G. conica-caliciformis 
nom. nov., a form which he considered as transitional between G. conica White and 
G. caliciformis (de Lapparent). However, as mentioned above, G. caliciformis is a 
probable synonym of G. contusa (Cushman), a species which is morphologically 
distinct from G. conica. This intermediate form described by Tilev may belong to 
G. orientalis sp. nov. 

Subbotina (1953) described as G. conica White, forms which are G. contusa scutilla 
Gandolfi and G. contusa patelliformis Gandolfi. 

Gandolfi (1955) considered G. conica White as a subspecies of G. stuarti (de Lap- 
parent), and thus changed its name to G. stuarti conica (White). However, as 
mentioned under G. stuarti stuarti, the morphological characters and stratigraphical 
ranges of the two species warrant their separation. Moreover, the form described by 
Gandolfi (1955) is different from both the holotype of White and the known forms of 
G. stuarti, and should be renamed and redescribed in more detail. Following 
Gandolfi (1955), Said & Kenawy (1956) incorrectly emphasized the relationship 
between G. conica White and G. stuarti (de Lapparent). 

Pessagno (i960, 1962) described as G. conica White, forms which were said to 
have a double keel on the early chambers of the last whorl, giving way to a single 
keel on the following chambers. Such forms probably belong to G. orientalis sp. nov. 

Globotruncana conica White is unique among the known spiroconvex Globotruncana 
species. No morphologically similar forms have yet been recorded from older strata, 
and thus very little is known about the evolutionary history of the species. However, 
it is possible that G. conica evolved from either G. sharawnaensis sp. nov. or 
G. orientalis sp. nov. The confused stratigraphical range of the species makes it 
difficult to decide, for the time being, although forms of G. sharawnaensis with an 
entirely single keel appear closely similar to G. conica. 

Hypotype. P.45520. 

Horizon and locality. Figured specimen from sample No. 16, Gebel Owaian 
section. 



go UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Stratigraphical range. White (1928) described G. conica from the Maestrich- 
tian Mendez formation of Mexico. However, he stated that the species ranges from 
the lower to the uppermost Cretaceous (Tamaulipas-Mendez formations) of Mexico, 
which is rather strange, as most of these Globotruncana species have very short 
ranges. Apparently he had confused the species with superficially similar Globo- 
truncana and Praeglobotruncana species which occur in older strata. Globotruncana 
conica was later described from the Middle and Upper Maestrichtian of S.E. Turkey 
(Tilev 1952) and form the Maestrichtian of northern Sinai, Egypt (Said & Kenawy 
1956). It was also stated to occur in the Maestrichtian of northern Italy (Cita 1948, 
1955, and Bolli & Cita 1960a) ; from the Upper Santonian-Lower Campanian of 
Trinidad (Bolli 1957, where the same author also recorded a form he described as 
G. cf. conica White in the Campanian-Maestrichtian of the same area) ; and from the 
upper part of the Mendez shale of Mexico (Hay i960). 

In the Esna-Idfu region G. conica White is rare to common in the Middle Maestrich- 
tian G. gansseri Zone. 



Globotruncana contusa contusa (Cushman) 
(PI. 7, figs. 2a-y; PI. 11, figs. la, b) 

1926a Pulvinnlina area Cushman var. contusa Cushman : 23 (no figs.). 

1927a Globotruncana area Cushman var. contusa (Cushman) ; Cushman : 169 (no figs.). 

J 939 Globotruncana area (Cushman) var. contusa (Cushman) ; Morozova : 80, pi. 1, figs. 1-3. 

1946 Globotruncana area (Cushman) var. contusa (Cushman) ; Cushman : 150-151, pi. 62, 
figs. ba-b. 
? 1946 Globotruncana conica White ; Keller : 102-103, pi. 3, figs. 4, 5. 

1948 Globotruncana area (Cushman) var. contusa (Cushman) ; Di Napoli : 21-22, text-figs. 
2a-c. 

1951 Globotruncana {Globotruncana) contusa (Cushman) ; Noth : 79, pi. 8, figs, ija-c. 

1951 Globotruncana contusa (Cushman) ; Bolli : 196, pi. 34, figs. 7-9, text-fig. if. 

1953 Globotruncana contusa (Cushman) ; Subbotina (pars) : 192—194, pi. 2, figs. 3a-e ; 
pi. 12, figs. 2a-c (non figs. ia-c). 
? 1954 Globotruncana contusa (Cushman) ; Nakkady & Osman : 78-79, text-figs. Aa-c. 

!955 Globotruncana contusa contusa (Cushman) ; Gandolfi : 53, pi. 4, figs. 3a-c. 

1956 Globotruncana contusa (Cushman) ; Wicher : 136, pi. 12, figs. 5, 6. 

1956a M arginotruncana contusa (Cushman) Hofker : 53, text-fig. 9. 

1960a Globotruncana (M arginotruncana) contusa (Cushman) ; Hofker : 225, text-figs. Z2a-c. 
? 19600 Globotruncana contusa (Cushman) ; Hofker : 586, text-fig. 1, drawing No. 15. 

i960 Globotruncana contusa (Cushman) ; Olsson : 50, pi. 10, figs. 25, 26. 

i960 Globotruncana contusa (Cushman) ; Vinogradov : 311, pi. 4, figs. 23a-24c ; pi. 5, 
figs. 25a-c. 
? 1962 Globotruncana (M arginotruncana) contusa (Cushman) ; Hofker : 1062, text-fig. 7A. 

Emended diagnosis. A Globotruncana with large highly spiroconvex test, 
distinctly folded surface, roughly angular, polygonal periphery, flat to slightly 
concave ventral side, sharply cut rectangular chambers on ventral side, radial, 
depressed ventral sutures, two well-developed marginal keels and almost horizontal 
peripheral band. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 91 

Description. (Specimen, PI. 7, figs. za-c). Test large, robust, spiroconvex with 
a sharply angular, polygonal outline and a peculiarly shaped, folded surface ; 
dorsal side highly trochospirally coiled, with bluntly curved convex folds radiating 
from the apex and shallowly concave, broader depressions running between the 
radiating folds, and widening away towards the base ; ventral side concave ; 
equatorial periphery roughly pentagonal with blunt corners, gently undulating and 
very weakly, if at all, lobate ; periphery with two well-developed, heavily beaded 
keels, enclosing a relatively wide, almost horizontal, slightly depressed peripheral 
band ; axial periphery subangular, distinctly truncate ; chambers, on the dorsal 
side 23, arranged in 4 dextrally coiled whorls ; they increase moderately and regu- 
larly in size till shortly before the beginning of the last whorl where they start to 
enlarge very rapidly and to change in shape ; the initial chambers are small, inflated, 
globigerine ; they increase moderately in size and are followed by relatively large, 
globular, inflated chambers which increase more rapidly in size, and become highly 
undulating and strongly elongated in the direction of coiling towards the end of the 
penultimate whorl ; the last whorl is composed of 4, very long, very narrow, 
broadly curved, roughly oblong, undulating chambers which are extremely elongated 
in the direction of coiling ; on the ventral side the chambers are 4, very large, 
angular, roughly oblong, very narrow, strongly elongated in the direction of coiling 
with their surfaces gently sloping towards the umbilicus ; sutures on the dorsal side 
slightly curved, faintly raised and delicately beaded in the early part, strongly 
curved, undulating, raised, thickened and heavily beaded later ; on the ventral side 
the sutures are straight, radial and depressed ; umbilicus rhombodial in outline, 
relatively wide, deep, surrounded by beaded umbilical ridges and covered by complex 
tegilla of which remnants are still preserved ; primary apertures interiomarginal, 
umbilical ; tegilla, with accessory apertures, only poorly preserved ; wall calcareous, 
perforate except for the imperforate keels, peripheral band and tegilla ; surface 
delicately papillose especially on the early part and on the ventral side. 

Dimensions of described specimen. 
Maximum diameter = 070 mm. 
Minimum diameter = 0-50 mm. 

Thickness = 0-45 mm. 

Main variation. 

1. Chambers 16-25, arranged in 3-4 or rarely 5 whorls, usually dextrally coiled, 

but sinistral forms also occur (out of 25 specimens picked at random, 1 
coiled sinistrally) . 

2. Chambers in the last whorl 4-5. 

3. The two keels are either equally developed throughout or the ventral one 

becomes slightly reduced on the last chamber. 

Remarks. Globotruncana contusa contusa was first described by Cushman (1926) 
as a variety of Pulvinulina area Cushman = Globotruncana area (Cushman), but 
no figures were given until 1946, when Cushman figured the dorsal and lateral views 
of the holotype. 



92 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Glaessner (1937a) raised Cushman's variety to specific rank, but again gave no 
figures. He was followed by Cita (1948), Bolli (1951), Noth (1951), Subbotina 
(1953), Ayala (1954), Nakkady & Osman (1954) and Troelsen (1955), but the figures 
given by both the first and last authors are different from Cushman's holotype. 

Gandolfi (1955) described two new subspecies of G. contusa (Cushman) and thus 
changed its name to G. contusa contusa, to distinguish it from G. contusa patelliformis 
Gandolfi and G. contusa scutilla Gandolfi. Hofker (1956a, 1960a, 1962a) assigned 
the present from to his genus Marginotruncana which is a junior synonym of Globo- 
truncana as stated above. Globotruncana conica var. plicata White 1928 is probably 
a junior synonym of G. contusa contusa (Cushman), but White's brief description does 
not allow a definite decision without examination of his holotype. Similarly, 
comparison of oriented thin sections of G. contusa (Cushman) with the holotype 
of Rosalina linnet mut. caliciforme de Lapparent 1918, and with Globotruncana linnei 
caliciformis (de Lapparent) of Vogler (1941), showed the possibility that G. contusa 
(Cushman) 1926 may be a junior synonym of G. caliciformis (de Lapparent) 1918. 
However, examination of several samples from the type locality of de Lapparent 
(The Hendaye region of southwestern France) is needed before any decision can be 
taken, as his original description is very brief, and his figure is only of a thin section. 
On the other hand, forms described as G. caliciformis by authors are different from 
the holotype of de Lapparent (1918) and the hypotype of Vogler (1941), and should 
be renamed and redescribed in more detail. Similarly, G. contusa (Cushman) of 
Troelsen (1955) is different from the holotype of Cushman (1926), and should also be 
renamed and redescribed ; the form figured by Berggren (1062) as G. contusa is 
doubtfully related to Troelsen's form, and is completely different from the holotype 
of Cushman. 

Globotruncana contusa contusa (Cushman) is believed to have evolved from G. 
fornicata fornicata Plummer through G. contusa witwickae subsp. nov. as suggested 
by the morphological characters and stratigraphical ranges of these forms. However 
Gandolfi (1955) suggested the evolution of G. contusa contusa (Cushman) from 
G. contusa patelliformis Gandolfi although he admitted its relationship to G. fornicata 
fornicata Plummer. 

Hypotypes. P.45521. 

Horizon and locality. Figured specimens, from sample No. 18, W. El- 
Sharawna section. 

Stratigraphical range. Globotruncana contusa contusa (Cushman) was describ- 
ed from the Maestrichtian Mendez shale of Mexico, and was later recorded from the 
same formation by Cushman (1927, 1946), White (1928), and Hay (i960). It was 
also recorded from the Maestrichtian of the U.S.S.R. (Morozova 1939, Keller 1946, 
Subbotina 1953) ; the Campanian-Maestrichtian of Austria and Switzerland 
(Noth 1951) ; the Maestrichtian of Trinidad (Bolli 1951, I957«) ; the Maestrichtian 
of Qabeliat and the Campanian-Maestrichtian of the Sudr sections, Sinai, Egypt 
(Nakkady & Osman 1954) ; the Maestrichtian Colon shale of northeastern Colombia 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 93 

(Gandolfi 1955) ; the Lower and Upper Maestrichtian of the Gamsa Basin, Austria 
(Wicher 1956) ; the Lower-Upper Maestrichtian boundary, Cr 4 -Mb, at Leon, 
Belgium (Hofker 1956a) ; the Lower and Upper Maestrichtian of the Atlantic 
Coastal Plain (Olsson i960) ; the Maestrichtian of the Prahova Basin, Romania 
(Vinogradov i960) ; and from the type Maestrichtian of Holland (Hofker 1960a, 
1962a). 

In the Esna-Idfu region, G. contusa contusa appears in the basal part of the 
G. gansseri Zone. It gradually increases in numbers upwards in the section, to 
flood this zone, and then fades out gradually, dying out completely in the overlying 
G. esnehensis Zone. No typical representatives of this subspecies were recorded in 
the Lower Maestrichtian G. fornicata Zone, which is flooded with transitional stages 
between the G. fornicata and G. contusa groups (e.g. G. contusa witwickae) ; while only 
rare forms were recorded throughout the G. esnehensis Zone. 

All reliable references show that G. contusa contusa ranges throughout the Middle 
and Upper Maestrichtian. All records of this subspecies from rocks older than the 
Middle Maestrichtian are probably confused with one of the other subspecies or are 
erroneous. 

Globotruncana contusa patelliformis Gandolfi 

(PL 8, figs, la-c) 

1955 Globotruncana (Globotruncana) contusa patelliformis Gandolfi : 54-55, pi. 4, figs. la-c. 
1961 Globotruncana contusa cf. patelliformis Gandolfi ; Corminboeuf : 112, pi. 1, figs. za-c. 

Description. Test large, robust ; trochospiraly coiled in the form a of high, 
truncated cone with a subcircular, wide base ; dorsal side very highly raised, and 
distinctly coned ; ventral side flat or even slightly concave as the sides gently slope 
towards the umbilicus ; equatorial periphery almost circular, slightly lobate, with 
two well-developed, heavily beaded marginal keels which become much closer on the 
penultimate chamber and reduced to a single, limbate, non-beaded keel on the last 
one ; the two keels enclose an almost horizontal and relatively wide peripheral 
band which is gradually reduced towards the last chamber ; axial periphery sub- 
angular, truncate ; chambers on the dorsal side are not all clear, probably 14 in 
number, arranged in 3 dextrally coiled whorls ; initial chambers small, indistinct, 
roughly globular, weakly inflated, increasing slowly in size and followed by crescentic, 
inflated chambers which are strongly elongated in the direction of coiling and 
increasing very rapidly in size ; the last whorl is composed of 4 very long, narrow, 
slightly undulating, crescentic chambers which are distinctly elongated in the 
direction of coiling and increasing slowly in size ; on the ventral side the chambers 
are 4, very long, narrow, distinctly elongated and strongly overlapping ; the very 
long sutures on the dorsal side are distinctly curved, strongly raised and heavily 
beaded especially in the early part ; on the ventral side the sutures are short, strongly 
curved forward, raised and beaded ; umbilicus roughly rectangular in outline, wide, 
deep, surrounded by raised, beaded ridges and covered by complex tegilla of which 
remnants are still preserved ; primary apertures interiomarginal umbilical ; tegilla, 



94 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

with accessory apertures, only poorly preserved ; wall calcareous, perforate, 
except for the imperforate keels, peripheral band and tegilla ; surface generally 
smooth but with a few scattered papillae on the dorsal side especially in the early part. 

Dimensions of described specimen. 

Maximum diameter = 0-52 mm. 

Minimum diameter = 0-49 mm. 

Thickness = 0-40 mm. 

Main variation. 

1. Chambers 14-21, arranged in 3-4 whorls, which are generally dextrally coiled 

(all the specimens studied coiled dextrally). 

2. Chambers in the last whorl 4-5, most commonly 4, slightly to moderately 

undulate and slowly to moderately increasing in size ; the last chamber is 
sometimes slightly smaller than the penultimate. 

Remarks. Globotruncana contusa patelliformis is distinguished from G. contusa 
contusa by its more regular, far less plicated, subconical test ; its narrow elongate, 
fornicata-type chambers on the ventral side ; strongly curved forward, raised and 
beaded ventral sutures and distinctly elongate early chambers. It is also distinguish- 
ed from the other members of the G. contusa group by the shape of its ventral cham- 
bers and sutures and its robust, regular test. 

Globotruncana contusa patelliformis is believed to have evolved from G. fornicata 
fornicata Plummer through G. adamsi sp. nov., as suggested by their morphological 
characters and stratigraphical distribution. The early part of G. contusa patelli- 
formis closely resembles G. adamsi, and the ventral side of the two forms is also very 
similar. However, Gandolfi (1955) suggested the evolution of G. contusa patelli- 
formis from G. contusa scutilla which can be considered a very small G. contusa 
patelliformis, but no transitional stages between these two subspecies were recorded 
in the present study. Gandolfi also suggested that G. contusa patelliformis had 
evolved into G. contusa contusa (Cushman) by the development of the sharply cut 
polygonal periphery, plicated dorsal side, and depressed ventral sutures. 

Specimens of G. contusa patelliformis Gandolfi, from the Esna-Idfu region, con- 
form well with the original description and figures of the holotype, and with topo- 
types kindly forwarded to the present author by Dr. R. Gandolfi. 

Hypotype. P. 45522. 

Horizon and locality. Figured specimen from sample No. 18, W. El-Sharawna 
section. 

Stratigraphical range. Gandolfi (1955) described G. contusa patelliformis 
from the Colon shale of northeastern Colombia, and gave its range as Campanian- 
Maestri chtian. However, analysis of the planktonic Foraminifera of the Colon 
shale, described by Gandolfi, suggests a Maestrichtian age for the whole formation. 

Corminboeuf (1961) recorded the present subspecies from the Maestrichtian of 
Switzerland. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 95 

In the Esna-Idfu region, G. contusa patelliformis occurs in the basal part of the 
Middle Maestrichtian G. gansseri Zone, where it increases gradually upwards in the 
section to flood the middle and upper parts of this zone and then fades out gradually 
in the overlying G. esnehensis Zone before dying out completely in the upper part of 
the latter zone. 

Globotruncana contusa scutilla Gandolfi 

1955 Globotruncana {Globotruncana) contusa (Cushman) scutilla Gandolfi : 54, pi. 4, figs. la-c. 

Remarks. A few specimens referable to the present subspecies were recorded 
from the G. fornicata Zone. Morphologically they appear to be so closely similar 
to G. contusa patelliformis that they could be considered small forms of it, despite the 
great difference in size. However, as it was only recorded from the G. fornicata 
Zone of the sections studied, and was stated by Gandolfi (1955) to appear in north- 
eastern Colombia much earlier in the succession than G. contusa patelliformis (the 
former appears in the Coniacian while the latter appears in what he considered 
Campanian), it was found advisable to treat it separately. 

G. contusa scutilla (if treated separately from G. contusa patelliformis) is believed 
to have evolved from G. fornicata fornicata (Plummer) into G. contusa patelliformis 
Gandolfi. 

Hypotype. P.45523. 

Stratigraphical range. Gandolfi (1955) recorded the present subspecies as 
ranging throughout the upper part of the Manaure shale and the basal part of the 
Colon shale of northeastern Colombia, which he considered as Coniacian-Lower 
Campanian. However, as previously mentioned, all the Colon shale is probably 
Maestrichtian in age. 

In the Esna-Idfu region G. contusa scutilla occurs as common to rare in the 
Lower Maestrichtian G. fornicata Zone only. 



Globotruncana contusa witwickae subsp. nov. 

(PI. 7, figs, la-c) 

Diagnosis. A Globotruncana contusa (Cushman) with much lower spire, less 
plicated surface and less elongated chambers on dorsal side. 

Description. Test large, robust, spiroconvex, coiled in a relatively high trocho- 
spire ; dorsal side moderately convex, gently plicate and undulate ; ventral side 
almost flat and weakly inflated ; equatorial periphery bluntly polygonal, with two 
well-developed, heavily beaded, marginal keels which enclose a narrow, slightly 
inclined peripheral band and tend to weaken towards the last chamber where the 
ventral keel is completely reduced ; axial periphery subangular, subtruncate ; 
chambers on the dorsal side 17, arranged in 3 dextrally coiled whorls ; initial chambers 
very small, globular, weakly inflated, increasing very slowly in size, followed by much 



96 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

larger, subglobular, inflated chambers which tend to be roughly crescentic towards 
the last whorl and which increase moderately in size ; the last whorl composed of 5 
large, narrow, distinctly elongated chambers, roughly crescentic in the early part, 
irregular, folded and undulate in the last two chambers, which increase moderately 
in size although the last chamber is slightly smaller than the penultimate ; the 5 
chambers on the ventral side are large, angular, roughly rectangular, strongly 
elongated and increase moderately in size except for the last one ; sutures on the 
dorsal side short, curved, beaded in the early part and distinctly elongated, curved, 
undulated, raised, thickened and beaded later ; on the ventral side the sutures are 
slightly curved in the early part, straight, radial and depressed in the later ; umbili- 
cus roughly stellate in outline, relatively wide, deep, bordered by thick beaded 
ridges which fade out gradually towards the last chamber ; it is covered by complex 
tegilla of which remnants are still preserved ; primary apertures interiomarginal, 
umbilical ; tegilla, with accessory apertures, only poorly preserved ; wall calcareous, 
perforate except for the imperforate keels, peripheral band and tegilla ; surface 
delicately papillose, especially in the early part and on the ventral side. 

Dimensions of holotype. 

Maximum diameter = 070 mm. 

Minimum diameter = 0-54 mm. 

Thickness = 0-31 mm. 

Remarks. This form represents the maximum development of a whole series of 
transitional stages between G. fornicata fornicata Plummer and G. contusa contusa 
(Cushman). It could neither be included in the former species, although it occurs 
with it, nor in the latter as it is morphologically slightly different and stratigraphical- 
ly older. It is more closely related to G. contusa contusa (Cushman) of which it is 
therefore considered a subspecies. 

Pozaryski & Witwicka (1956) mentioned the occurrence of what they described as 
G. fornicata var. contusa in the Upper Campanian of the Lublin Basin, central 
Poland, but gave no figure or description. Their form may belong to the present 
subspecies or it may be transitional to G. fornicata fornicata Plummer. However, as 
all forms of G. fornicata which show transitional characters to G. contusa are included 
in the present subspecies, Pozaryski & Witwicka's form is considered to belong here. 
This subspecies is named after Dr. E. Witwicka of the Geological Institute, Rako- 
wiecka, Poland. 

Holotype. P. 45524. 

Paratypes. P.45525. 

Horizon and locality. Holotype and paratypes, from sample No. 4, Abou 
Saboun section. 

Stratigraphical range. The subspecies is restricted in the present sections to 
the Lower Maestrichtian G. fornicata Zone, where it is common to abundant. The 
form described by Pozariski & Witwicka (1956) as G. fornicata var. contusa which 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 97 

probably belongs to the present subspecies, was recorded from the Upper Campanian 
of central Poland. Records of G. contusa contusa (Cushman) from rocks older than 
the Middle Maestrichtian may be of G. contusa witwickae. 

Globotruncana cf. convexa Sandidge 
(PL i, figs, sa-c) 

1932 Globotruncana convexa Sandidge : 285, pi. 44, figs. 9-1 1. 

Description. Test small, biconvex, coiled in a low trochosphire ; dorsal side, 
moderately arched, ventral side weakly inflated and slightly protruding ; equatorial 
periphery roughly ovoid or rather quadrate, distinctly lobate, with two well-develop- 
ed, heavily beaded keels enclosing a wide, inclined peripheral band ; axial periphery 
truncate ; chambers on dorsal side 15, arranged in 3 dextrally coiled whorls ; the 
initial chambers are very small, globigerine, inflated and increase slowly in size ; 
the last whorl is composed of 4 large, crescentic chambers which are distinctly 
flattened, elongated in the direction of coiling and increase moderately in size ; on the 
ventral side the chambers are 4, large, ovoid, weakly inflated and slightly overlapping ; 
sutures on the dorsal side curved, raised and heavily beaded ; on the ventral side the 
sutures are strongly curved forward, slightly raised and beaded ; umbilicus roughly 
quadrangular in outline, wide, deep, bordered by raised, beaded ridges and covered 
by complex tegilla of which remnants are still preserved ; primary apertures interio- 
marginal, umbilical ; tegilla with accessory apertures only poorly preserved ; 
wall calcareous, perforate except for the imperforate keels, peripheral band and 
tegilla ; surface delicately papillose in the early part, becoming smoother towards 
the last chamber. 

Dimensions of described specimen. 
Maximum diameter = 0-40 mm. 
Minimum diameter = 0-30 mm. 

Thickness = 0-17 mm. 

Remarks. Cushman & Hedberg (1941) followed by Cushman & Deaderick (1944), 
Cushman (1946), Cita (1948), Hagn (1953) and Graham & Clark (1961) considered 
G. convexa Sandidge to be a junior synonym of G. fornicata Plummer. However, as 
can be seen from the original description and figures of Sandidge (1932) and from the 
samples here studied, G. convexa is more closely related to G. area (Cushman) than 
to G. fornicata Plummer and should be considered separately. 

The specimens here described as G. cf. convexa Sandidge differ from the holotype 
in being less convex on the dorsal side and in having slightly raised ventral sutures. 
Sandidge described the ventral keel on the holotype as poorly developed, while on 
the specimen here figured the two keels are both well-developed, although the 
tendency towards a less developed ventral keel was clearly observed. 

Globotruncana convexa is believed to have evolved from G. area (Cushman) by a 
reduction in size of test and in the number of chambers, and by the development of 
surface rugosity. 

Hypotype. P.45526. 



98 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Horizon and locality. Figured specimen, from sample No. 20, W. El- 
Sharawna section. 

Stratigraphical range. Globotruncana convexa was first recorded by Sandidge 
(1932) from the Maestrichtian Ripley formation of Alabama. 

In the Esna-Idfu region G. cf. convexa ranges throughout the Maestrichtain, 
being common to abundant in the G. fornicata and the G. gansseri Zones, gradually 
fades out towards the top part of the latter zone and completely dies out in the 
overlying G. esnehensis Zone. 

Globotruncana esnehensis Nakkady & Osman 

(PI. 12, figs, za-d) 

1950 Globotruncana area (Cushman) var. esnehensis Nakkady : 690, pi. 90, figs. 23-26. 
1954 Globotruncana esnehensis Nakkady & Osman : 79, pi. 19, figs. 3a— c. 
? 19566 Marginotruncana stuarti (de Lapparent) ; Hofker : 332-333, text-fig. 23. 
1956 Globotruncana caliciformis Vogler ; Said & Kenawy : 150, pi. 5, figs. i8a-c. 
1956 Globotruncana intermedia Bolli ; Said & Kenawy : 151, pi. 5, figs, i^a-c. 
1961 Globotruncana esnehensis Nakkady, Said & Kerdany : 331, pi. 2, figs. i2a-c. 

Emended diagnosis. A Globotruncana with large, spiroconvex test ; broadly- 
domed dorsal side and flat to slightly convex or even slightly concave, undulating 
ventral one ; well-developed beaded, single keel ; chambers increasing slowly in size, 
almost petaloid on dorsal side and subglobular to ovoid on ventral side ; slightly 
curved, raised, beaded dorsal sutures and radial depressed ventral ones ; large 
umbilicus and distinctly beaded umbilical ridge ; slightly to moderately lobulate 
equatorial periphery and angular, acute axial one; peculiar apertural face of last 
chamber and delicately papillose surface. 

Description. Test large, almost circular in outline, spiroconvex, coiled in a 
relatively high trochospire ; dorsal side broadly domed ; ventral side almost flat or 
even slightly concave, although the chambers are weakly inflated ; equatorial 
periphery circular, moderately lobate with a single well-developed, beaded keel ; 
axial periphery angular, acute ; chambers on the dorsal side 19, arranged in three 
whorls which are coiled dextrally and very tightly ; they increase slowly and 
regularly in size, except the last, which is slightly smaller than the penultimate ; 
initial chambers small, inflated, globigerine, followed by relatively large, subglobular, 
moderately inflated ones ; the last whorl is composed of 6 large, typically petaloid 
chambers which moderately overlap and increase slowly in size ; on the ventral side 
the chambers are 6, large, roughly ovoid, slightly inflated and increase so slowly in 
size that they all appear to be roughly equal ; each chamber is weakly inflated at its 
centre and slopes gently towards the suture on each side giving the ventral surface a 
gently undulating appearance ; sutures on the dorsal side are very slightly curved or 
almost straight in the early part, very gently curved in the later part, raised and 
distinctly beaded ; on the ventral side they are radial, depressed and delicately 
beaded ; umbilicus hexagonal in outline, wide, relatively deep, surrounded by a 
beaded umbilical ridge and covered by complex tegilla of which remnants are still 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 99 

preserved ; primary apertures interiomarginal, umbilical ; tegilla with accessory 
apertures only poorly preserved ; wall calcareous, perforate except for the imperfo- 
rate keel and tegilla ; surface delicately papillose especially on the early part and on 
the ventral side. 

Dimensions of described specimen. 
Maximum diameter = 0-50 mm. 

Minimum diameter = 0-44 mm. 

Thickness = 0-27 mm. 

Main variation. 

1. Chambers 15-21, arranged in 3-4 whorls usually dextrally coiled, but sinistral 

forms also occur (out of 500 specimens selected at random, 28 coiled sinis- 
trally). 

2. The last whorl is composed of 5-7 chambers, normally 6, varying in shape from 

typically petaloid to slightly elongate or even roughly rectangular, and in 
the degree of inflation on the ventral side which may give it a weakly or 
distinctly undulating appearance. 

Remarks. Globotruncana ensehensis was first described by Nakkady (1950) as 
a variety of Globotruncana area (Cushman). Nakkady & Osman (1954) realizing the 
great difference between this form and G. area (Cushman), quite justifiably raised it 
to specific rank. Hofker (1956c: 75) and Berggren (1962 : 31) considered G. esnehen- 
sis as a junior synonym of Abathomphalus intermedia (Bolli), but the two species are 
too remote to be related to each other. Again, Said & Kenawy (1956) described as 
G. intermedia Bolli, and G. caliciformis Vogler, forms which are actually G. esnehensis. 

The evolutionary history of G. esnehensis is not clearly known because its strati- 
graphical range has been somewhat confused. However, its morphological similarity 
to both G. orientalis sp. nov. and G. fareedi sp. nov., which appear earlier in the 
section, may suggest its evolution from one of these species, although no direct 
evidence was recorded. Again, it is possible that G. esnehensis has evolved from 
G. conica White, although the morphological characters and stratigraphical range of 
the latter species have been very much confused. 

Specimens of G. esnehensis, from the Esna-Idfu region, conform well with the 
holotype of G. area (Cushman) var. esnehensis of Nakkady (1950) (B.M.N.H., 
P. 41780), the paratypes (P.41781), and with the description and figures of Nakkady 
& Osman (1954). 

Hypotype. P.45527. 

Horizon and locality. Figured specimen, from sample No. 17, W. El- 
Sharawna section. 

Stratigraphical range. Nakkady (1950) described G. area (Cushman) var. 
esnehensis from the Maestrichtian Esna shale of the Abu Durba section, western 
Sinai, Egypt. He also reported it to be frequent in the Maestrichtian Globotruncana- 
Guembelina Zone of the Abu Durba and Mellaha sections and to flood the Maestrich- 
tian chalk of Gebel Duwi. 



ioo UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Nakkady & Osman (1954) described G. esnehensis from the Campanian-Maestrich- 
tian of southern and western Sinai, Egypt and it was recorded from the Maestrichtian 
of northern Sinai (Said & Kenawy 1956), the Maestrichtian of the Farafra Oasis 
(Said & Kerdany 1961) and from the Lower Maestrichtian of northwestern Germany 
and Holland (Hofker 1956&). 

In the Esna-Idfu region G. esnehensis appears in the basal part of the Middle 
Maestrichtian Globotruncana gansseri Zone as a common form, increases gradually 
upwards in the section, flooding the upper part of the Maestrichtian and character- 
izing the Globotruncana esnehensis Zone, the upper part of which is truncated by the 
disconformity separating it from the overlying basal Tertiary rocks. 

Globotruncana far eedi sp. nov. 
(PI. 9, figs. 4a-d) 

? 1946 Globotruncana rosetta (Carsey) ; Keller : 102, pi. 2, figs. 17-19, pi. 3, fig. 6. 
? 1955 Globotruncana rosetta insignis Gandolfi : 67, pi. 6, figs. 2a-c. 
1956 Globotruncana falsostuarti Sigal ; Knipscheer : 54, pi. 4, figs. 13a, b, i6a-c, text-fig. 4. 

Diagnosis. A Globotruncana with large, circular, biconvex test ; distinctly 
lobate periphery ; characteristic, roughly quadrangular chamber shape on both 
sides ; entirely single keel ; short, nearly radial, depressed, sutures on ventral side ; 
raised, thickened, beaded, imbricate umbilical ridges, and wide, peculiarly-shaped 
umbilicus. 

Description. Test large, circular, biconvex ; dorsal side arched ; ventral side 
moderately protruding ; periphery circular, distinctly lobate, transversally acute, 
with a single well-developed, beaded keel ; chambers on the dorsal side 18, arranged 
in 3 dextrally coiled whorls ; initial chambers small, inflated, globigerine, followed by 
roughly quadrangular chambers which increase regularly in size ; the last whorl is 
composed of 6 large, quadrangular chambers which are very slightly elongated in the 
direction of coiling ; on the ventral side the 6 large, roughly quadrangular chambers 
are moderately inflated especially around the umbilicus, and taper out gradually 
towards the periphery ; sutures on the dorsal side slightly curved in the early part, 
nearly straight in the last part, raised and beaded ; on the ventral side the sutures 
are very slightly curved or nearly straight, radial and strongly depressed especially 
towards the periphery, while towards the umbilicus they are slightly raised, thickened 
and beaded before curving around the umbilicus and joining to form a much thick- 
ened, raised, beaded umbilical flange ; umbilicus wide, deep, roughly hexagonal, 
covered by complex tegilla of which remnants are still preserved ; primary apertures 
interiomarginal, umbilical ; tegilla with accessory apertures only poorly preserved ; 
wall calcareous, perforate, except for the imperforate keel and tegilla ; surface 
smooth and finely porous. 

Dimensions of holotype. 

Maximum diameter = 0-47 mm. 

Minimum diameter = 0-44 mm. 

Maximum thickness = 0-22 mm. 



in the esna-idfu region, nile valley, egypt 101 

Main variation. 

i. The test may be strongly or weakly biconvex. 

2. Chambers 18-24 arranged in 3-4 whorls, (all the specimens studied coiled 

dextrally) . 

3. The beading of the sutures and the keel may be heavy throughout or may fade 

out gradually towards the last chamber. 

4. The rate of growth may be slow and constant, leading to a regular increase in 

chamber size, or it may be rapid in the later stage, producing relatively 
bigger chambers in the last whorl. 

5. The dorsal surface of each of the chambers in the last whorl (not the dorsal 

side of the test) is flat, slightly convex, or even slightly concave. 

6. The umbilicus is moderate to large and the ventral sutures are either slightly 

or strongly depressed. 

Remarks. Globotruncana fareedi sp. nov. morphologically resembles both 
G. stuarti stuarti (de Lapparent) and G. esnehensis Nakkady & Osman. It is dis- 
tinguished from the former by its equally biconvex test, lobate periphery, quad- 
rangular rather than trapezoidal chambers on the dorsal side ; short, depressed 
radial sutures on the ventral side and less tangential ones on the dorsal ; its much 
wider umbilicus and imbricate umbilical flange. It differs from G. esnehensis in 
having a biconvex test, a much lower dorsal side and a more protruding ventral one, 
quadrangular chambers on the ventral side and less inflated ones on the dorsal, 
much wider umbilicus and an imbricate umbilical flange. Globotruncana falsostuarti 
Sigal has a similarly wide umbilicus and discontinuous umbilical flange, but is 
distinguished by its double keel and more protruding ventral side. 

Globotruncana fareedi sp. nov. was probably confused in the past with both 
G. rosetta rosetta (Carsey) and G. falsostuarti Sigal. However, G. rosetta rosetta is 
distinguished by its perfectly plano-convex, umbilico-convex test ; double keel on 
the early chambers of the last whorl, becoming single on the last chambers ; its flat 
crescentic chambers on the dorsal side, and angular conical, strongly protruding ones 
on the ventral ; its narrower umbilicus, and slightly rougher surface. The forms 
described as G. rosetta (Carsey) by Keller (1946) and as G. rosetta insignis by Gandolfi 
(1955) are not related to G. rosetta, but probably belong to the present species, 
although Gandolfi's form shows a flatter dorsal side and a slightly narrower umbilicus. 
Again, G. falsostuarti Sigal was so briefly described that its diagnostic features were 
not really known, and thus it has often been misinterpreted. The forms figured by 
Knipscheer (1956) as G. falsostuarti are different from Sigal's holotype, but may well 
belong to the present species, while the form described as G. rosetta pembergeri by 
Papp & Kupper (1953) most probably belongs to G. falsostuarti Sigal. Through the 
kindness of Dr. J. Sigal, the type specimens of G. falsostuarti, which are in his 
personal collection, were examined by the present author. This examination 
showed that : 

1. The holotype of G. falsostuarti is distinguished by its unequally biconvex test ; 
strongly protruding ventral side ; two closely spaced keels, the ventral one 
of which is slightly shifted towards the inner side of the test and is reduced 



io2 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

on the last chamber ; its highly beaded keels and dorsal sutures ; inclined 
peripheral band ; raised, beaded, discontinuous umbilical flange ; and 
inclined, raised, beaded ventral sutures. It is more closely related to 
G. area (Cushman) than to G. stuarti stuarti (de Lapparent). 
2. The paratypes of G. falsostuarti include forms belonging to G. stuarti stuarti 
(de Lapparent), G. conica White, G. esnehensis Nakkady & Osman and 
G. fareedi sp. nov. 
The similarity in the shape of the chambers and the sutures on both sides, the 
distinctly lobate, circular periphery and the entirely single keel, suggest that G. 
fareedi sp. nov. has possibly evolved from G. elevata (Brotzen) in early Maestrichtian 
time, although its evolution from G. stuarti stuarti (de Lapparent) is not excluded. 
Again, G. fareedi may have evolved into G. esnehensis Nakkady & Osman in early 
Middle Maestrichtian time by increasing the convexity of the dorsal side and flatten- 
ing the ventral side. The diagnostic features and stratigraphical ranges of these 
species favour these propositions. 

This species is named after Dr. Fareed El-Naggar of the National Institute of 
Management Development, Cairo. 

Holotype. P.45528. 

Paratypes. P. 45666. 

Horizon and locality. Holo- and paratypes, from Sample No. 24, W. El- 
Sharawna section. 

Stratigraphical range. G. fareedi occurs as rare to common in the L. Maestri- 
chtian G. fornicata Zone, common to abundant in the Middle Maestrichtian G. 
gansseri Zone, and dies out in the basal part of the Upper Maestrichtian G. esnehensis 
Zone. 

Globotruncana fornicata ackermanni Gandolfi 

(PL 14, figs. 3a-sd) 

1955 Globotruncana fornicata ackermanni Gandolfi : 42-43, pi. 2, figs. $a-jc. 
? 1958 Globotruncana fornicata ackermanni Gandolfi ; Ansary & Fakhr : 135, pi. 2, figs. i6a-c. 

Description. (Specimen, PI. 14, figs. \a-d.) Test small, biconvex, coiled in a 
low trochospire ; dorsal side slightly convex, moderately inflated, ventral side 
inflated, moderately protruding ; equatorial periphery roughly ovoid or rather 
quadrate, moderately lobate, with two well-developed, delicately beaded, slightly 
diverging, imbricate keels, enclosing a wide, slightly depressed peripheral band ; 
axial periphery globular, subtruncate ; chambers on the dorsal side 15, arranged in 3 
dextrally coiled whorls ; the initial ones are small, globular, inflated, increase 
slowly in size and are followed by relatively larger, globular, more inflated chambers 
which increase moderately in size ; the last whorl is composed of 4 large chambers 
which are subglobular in the early part, crescentic and strongly elongated in the 
direction of coiling in the later part and which increase rapidly in size ; the last 
chamber is very well-developed and constitutes about \ of the test ; on the ventral 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 103 

side the chambers are 4, large, subglobular in the early part, ovoid in the last chamber, 
strongly inflated and increase rapidly in size ; sutures on the dorsal side curved, 
raised, delicately beaded and merge into relatively shallow depressions from the 
periphery inwards towards the spiral suture ; on the ventral side the sutures are 
radial and depressed ; umbilicus irregular in outline, wide, deep and covered by 
complex tegilla of which remnants are still preserved ; primary apertures interio- 
marginal, umbilical ; tegilla, with accessory apertures, only poorly preserved ; 
wall calcareous, perforate except for the imperforate keels, peripheral band and 
tegilla ; surface rough, coarsely papillose. 

Dimensions of described specimen. 
Maximum diameter = 0-38 mm. 

Minimum diameter = 0-29 mm. 

Thickness = 0-22 mm. 

Variation. The main variation observed in G. fornicata ackermanni is in the 
degree of inflation of both sides, imbricate arrangement of keels, rate of growth and 
surface rugosity. 

Remarks. Globotruncaca fornicata ackermanni is believed to have evolved from 
G. fornicata fornicata Plummer by reduction in the size of test, greater inflation of 
the chambers, imbricate arrangement of keels and peripheral band and the develop- 
ment of surface rugosity. The form here figured (PL 14, figs, ^a-d) shows inter- 
mediate characters between the two subspecies and is thus considered as a transition- 
al stage. 

Hypotypes. P.45529. 

Horizon and locality. Figured specimes, from sample No. 4, Abou Saboun 
section. 

Stratigraphical range : Gandolfi (1955) described G. fornicata ackermanni 
from the Colon shale of northeastern Colombia, where he considered its range as 
Campanian-Lower Maestrichtian. It was also recorded from the Maestrichtian of 
Um El-Huetat section west of Safaga, Eastern Desert, Egypt (Ansary & Fakhr, 1958). 

In the Esna-Idfu region, G. fornicata ackermanni occurs as a common to abundant 
form in the Lower Maestrichtian G. fornicata Zone and dies out completely towards 
the top part of this zone. 

Globotruncana fornicata cesarensis Gandolfi 

(PL 13, figs. 3«~4c ; PL 14, figs. 6a-c) 

1955 Globotruncana fornicata cesarensis Gandolfi : 45, pi. 2, figs. loa-c. 

Description. (Specimen, PL 14, figs. 6a-c.) Test medium-sized, biconvex, 
coiled in a low trochospire ; dorsal side convex, moderately inflated, and slightly 
folded in the last chamber, ventral side slightly inflated ; equatorial periphery 
roughly ovoid, moderately lobate, with two well-developed, delicately beaded 



io 4 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

marginal keels enclosing a wide peripheral band which widens out towards the last 
chamber ; axial periphery truncate ; chambers on the dorsal side are not all clear but 
appear to be 15 in number, arranged in 3 dextrally coiled whorls ; initial chambers 
extremely small, globular, weakly inflated and increase slowly in size ; they are 
followed by slightly larger, globular inflated chambers which increase slowly in size 
up to the beginning of the last whorl where they start to enlarge very rapidly ; the 
last whorl is composed of 4 large, strongly inflated chambers which are roughly 
globular in the early part, crescentic and strongly elongated in the direction of coiling 
in the later part and increasing so rapidly in size that the last chamber constitutes 
about half the test ; on the ventral side the chambers are 4, subglobular in the early 
part, strongly elongated in the last chamber which constitutes about half of the test ; 
sutures on the dorsal side curved, raised, beaded, merging into relatively sharp 
depressions before joining the spiral suture ; on the ventral side the sutures are 
radial and depressed ; umbilicus irregular in outline, relatively wide, deep, bordered 
by weakly raised, delicately beaded umbilical ridges, and covered by complex tegilla 
of which remnants are still preserved ; primary apertures interiomarginal umbilical ; 
tegilla, with accessory apertures, only poorly preserved ; wall calcareous, perforate 
except for the imperforate keels, peripheral band and tegilla ; surface rough, 
delicately papillose, with the roughness decreasing gradually towards the last 
chamber. 

Dimensions of described specimen. 

Maximum diameter = 0-43 mm. 

Minimum diameter = 0-31 mm. 

Thickness = 0-25 mm. 

Variation. The main variation observed in this subspecies is in the degree of 
inflation of the chambers in the last whorl, the degree of surface plication on the 
dorsal side and in the surface roughness. 

Remarks. Globotruncana fomicata cesarensis was first described by Gandolfi 
(1955) and considered to represent a final stage in the evolution of the G. fornicata 
group, characterized by the reduction in the size of test and in the number of chamb- 
ers in the last whorl. The present study substantiates Gandolfi's conclusion, although 
his G. fornicata plummevae which he regarded as the ancestor of G. fornicata cesar- 
ensis, is here considered a junior synonym of G. fornicata fornicata Plummer. 

Specimens of G. fornicata cesarensis, from the Esna-Idfu region, conform well with 
Gandolfi's original description and figures. However, two distinct morphological 
types of this subspecies were recorded, one with a smooth test and a non-inflated 
dorsal side (e.g. PI. 13, figs. 30-c), the other with a moderately to distinctly inflated 
dorsal side and a rougher surface. The former type was clearly observed high in the 
section while the latter was found to flood the lower part. It is possible that further 
study may prove these types to be worthy of distinction. However, as such varia- 
tion was mentioned by Gandolfi (1955), and as the former type was found to be rather 
rare in the samples studied, the two forms are here assigned to the same subspecies. 

Hypotypes. P.45530. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 105 

Horizon and locality. Figured specimens, PI. 13, figs 3«-c from sample No. 
16, W. El-Sharawna section, figs, ^a-c, from sample No. 14, Gebel A 314 section ; 
PI. 14, figs. 6a-c, from sample No. 4, Abou Saboun section. 

Stratigraphical range. Gandolfi (1955) described this subspecies from the 
Colon shale of northeastern Colombia where he considered its range as Campanian- 
basal Maestrichtian. 

In the Esna-Idfu region, G. fornicata cesarensis floods the Lower Maestrichtian 
G. fornicata Zone, fades out gradually upwards in the section and occurs as a rare 
form in the basal part of the overlying G. gansseri Zone where it dies out completely. 

Globotruncana fornicata fornicata Plummer 
(PI. 13, figs. 5«-c, 6 ; PI. 14, figs. la-c) 

1931 Globotruncana fornicata Plummer : 198, pi. 13, figs. /\a-c, 5, 6. 

1951 Globotruncana fornicata Plummer ; Drooger : 7, pi. 1, figs. qa-c. 

J 953 Globotruncana fornicata Plummer ; Hagn : 98, pi. 8, figs. 8a-c, text-figs. 22, 23. 

1953 Globotruncana fornicata Plummer ; Subbotina : 184-185, pi. 8, figs. 3«-c, ? \a-y. 

1955 Globotruncana {Globotruncana) fornicata plummerae Gandolfi : 42, pi. 2, figs. $a-c, ? ^a-c. 

1961 Globotruncana fornicata Plummer ; Graham & Clark : 112, pi. 5, figs. 10a — c. 

1962 Globotruncana (Globotruncana) fornicata Plummer ; Pessagno : 362, pi. 4, figs. 4, 5, 11. 

1963 Globotruncana fornicata Plummer ; Lehmann : 148, pi. 7, figs. ia-2C ; ? ^a-^c ; text- 
figs, iv, w ; 3«, r, t 

Description. (Specimen, PI. 13, figs. 5«-c.) Test large, biconvex, coiled in a 
low trochospire ; dorsal side slightly convex, moderately inflated, ventral side 
slightly more inflated and relatively protruding ; equatorial periphery ovoid, 
slightly lobate, with two well-developed, delicately beaded diverging keels ; axial 
periphery truncate ; chambers on the dorsal side 17, arranged in 3 dextrally coiled 
whorls ; initial chambers very small, almost indistinct, globigerine, weakly inflated, 
increasing slowly in size ; they are followed by relatively larger, globular, slightly 
inflated chambers which also increase slowly in size till the beginning of the last 
whorl where they start to change their shape and rate of growth ; the last whorl 
constitutes most of the test and is composed of 4J large, long, narrow inflated, 
slightly folded, highly curved crescentic chambers ; on the ventral side the chambers 
are 4, kidney-shaped, moderately inflated and strongly overlapping ; sutures on the 
dorsal side are curved, raised, delicately beaded, tending to merge into relatively 
sharp depressions from the periphery inwards towards the preceding whorl (as in 
Plummer's description) ; on the ventral side the sutures are strongly curved forward, 
slightly raised and delicately beaded ; umbilicus roughly rhomboidal in outline, 
wide, deep, bordered by slightly raised delicately beaded ridges, covered by complex 
tegilla of which remnants are still preserved ; primary apertures interiomarginal, 
umbilical ; tegilla, with accessory apertures, only poorly preserved ; wall calcareous, 
perforate except for the imperforate keels, peripheral band and tegilla ; surface 
delicately papillose in the early part and on the ventral side, becoming smooth 
towards the last chamber ; the two keels enclose a relatively wide, depressed, 
slightly inclined peripheral band which is relatively narrow at the posterior part of 
test but widens out anteriorly as the keels diverge. 



106 upper cretaceous-lower tertiary foraminifera 

Dimensions of described specimen. 
Maximum diameter = 0-51 mm. 
Minimum diameter = 0-39 mm. 

Thickness = 0-24 mm. 

Main variation. 

1. Test medium-sized to large, subcircular to ovoid in outline. 

2. Dorsal side very slightly raised to moderately convex, gently plicate to 

slightly folded. 

3. Ventral side inflated, slightly to moderately protruding. 

4. Chambers 14-18, arranged in 2^-3 whorls, usually dextrally coiled (of 60 

specimens picked at random, 4 coiled sinistrally) . 

5. Usually 4 or 5 chambers in the last whorl : specimens with 3! or 6 chambers 

occur very rarely. 

6. The peripheral band varies in width and in degree of inclination towards the 

ventral side. 

7. The two keels can either be occasionally developed or the ventral keel may 

equally weaken towards the last chamber. 

8. The surface is generally smooth but is sometimes delicately papillose in the 

early part. 

Remarks. As was mentioned in part by Gandolfi (1955) Globotruncana fornicata 
Plummer (1931) and of authors, is actually a group of closely related forms. These 
are generally characterized by a biconvex, double-keeled test, small, globigerine, 
early chambers, and long, narrow highly arched later ones ; these are slightly to 
moderately plicate on the dorsal side and moderately to strongly overlapping on the 
ventral. They are also characterized by a slightly inclined peripheral band and 
dorsal sutures which merge into relatively sharp depressions from the periphery 
inwards. 

Gandolfi considered some of these related forms to be subspecies of G. fornicata, 
and described the following : 

Globotruncana fornicata fornicata Plummer 1931. 

Globotruncana fornicata plummer ae Gandolfi 1955. 

Globotruncana fornicata ackermanni Gandolfi 1955. 

Globotruncana fornicata cesarensis Gandolfi 1955. 

Globotruncana fornicata manaurensis Gandolfi 1955. 

However, Gandolfi's specimen described as G. fornicata fornicata Plummer 
differs from Plummer's original description and figures and may possibly be a 
distinct form. On the other hand, examination of topotypes of G. fornicata plum- 
merae, kindly presented by Dr. R. Gandolfi, proved their identity with G. fornicata 
fornicata Plummer from the Esna-Idfu region and with topotype material kindly 
sent by Dr. E. A. Pessagno, Jr., of the University of California. Thus G. fornicata 
plummer ae Gandolfi is considered to be a junior synonym of G. fornicata fornicata 
Plummer. 

The other forms described by Gandolfi are here recognized as valid subspecies. 
A new subspecies of G. fornicata was also discovered during the present study and 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 107 

named G. fornicata globulocamerata ; it is distinguished by a tendency to have 
globular chambers in the last whorl instead of the extremely elongated chambers of 
the central type. 

The lumping of these subspecies and their transitional forms as G. fornicata 
Plummer has confused the diagnostic features and stratigraphical range of G. 
fornicata fornicata. However, it is clearly distinguished by its biconvex test, 
extremely elongated chambers in the last whorl which are slightly plicate on the 
dorsal side and sometimes inflated towards their inner extremities, and strongly 
overlapping on the ventral side ; its curved, raised, beaded, ventral sutures and 
strongly diverging double keel. 

Glaessner (1937 : 43, text-fig. 5) suggested the evolution of G. fornicata Plummer 
from Rotalipora appenninica (Renz), in Coniacian-Santonian time through a yet 
unknown form. However, Bolli (1951) and Gandolfi (1955, pi. 10) suggested its 
evolution from G. lapparenti lapparenti (Brotzen) while Bronnimann & Brown (1956) 
suggested that it evolved from G. imbricata Mornod. Moreover, Gandolfi (1955) 
suggested the evolution of G. fornicata fornicata Plummer from G. fornicata manaur- 
ensis by the gradual reduction of the tight coiling of the chambers, by the reduction 
in the number and degree of overlap of chambers, and by the anterior divergence of 
the two keels. It is also evident that members of the G. fornicata group have 
gradually evolved into the corresponding members of the G. contusa group, through 
various transitional stages, as was partly mentioned by Glaessner (1937), Bolli (1951), 
Gandolfi (1955), and Bronnimann & Brown (1956), and is clearly documented in the 
present study. 

G. fornicata fornicata is believed to have evolved into G. contusa contusa through 
G. contusa witwickae subsp. nov., and into G. contusa sensu Troelsen through G. 
fornicata globulocamerata subsp. nov. 

Hypotypes. P. 45531. 

Horizon and locality. Figured specimens, PI. 13, figs. 5«-c, from sample No. 
14, G. A 314 ; fig. 6, from sample No. 3, Abou Saboun section ; PI. 14, figs, la-c from 
sample No. 4 Abou Saboun section. 

Stratigraphical range. Globotruncana fornicata fornicata Plummer was first 
described from the Upper Taylor (Campanian) Formation of Texas (Plummer 1931, 
sta. 226-T-8) and was recorded as very common to abundant in Taylor and Navarro 
strata which, according to Bolli (1957, 1959), corresponds to the Upper Santonian- 
Lower Maestrichtian of Western Europe. It was recorded from the same horizon 
by Cushman & Todd (1943), Cushman (1944, 1946, 1948), and by Frizzell (1954) who 
showed that it ranges throughout the whole Taylor and Lower Navarro groups, 
being most abundant in the upper Taylor beds, and that it never occurs below the 
base of the Taylor formation. Albritton & Phleger (1937) restricted its range to the 
Taylor group only, while Bronnimann & Brown (1956) recorded its range as Coniacian 
to Campanian, possibly Maestrichtian. Hagn (1953) described it from the Upper 
Campanian of Germany, Barr (1962) from the Campanian of the Isle of Wight, 



108 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

England, and Lehmann (1963) from the Coniacian-Campanian of the Tarfaya 
province, western Morocco. 

Other authors, by misidentifying Plummer's species, or by confusing it with other 
subspecies, gave various ranges between Upper Turonian and Lower Maestrichtian, 
although it was clearly stated (Frizzell 1954) that in the type locality it was not 
found below the Upper Santonian (base of the Taylor formation) . 

In the Esna-Idfu region Globotruncana fornicata fornicata Plummer floods the 
basal part of the Sharawna shale formation, characterizing the G. fornicata Zone, to 
which it is restricted and in which it constitutes, together with its subspecies, the 
bulk of the planktonic Foraminifera. It fades out gradually upwards in the section 
disappearing completely below the overlying G. gansseri Zone. 



Globotruncana fornicata globulocamerata subsp. nov. 
(PL 13, figs, za-c ; PL 14, figs. 2a-c) 

Diagnosis. A Globotruncana fornicata with globigerine character of early 
chambers extending to most of last whorl, final one or two chambers only are 
distinctly elongated in direction of coiling. 

Description. (Holotype, PL 14, figs, za-c.) Test medium sized, biconvex, 
coiled in a low trochospire ; dorsal side gently arched and moderately inflated, 
ventral side slightly inflated and weakly protruding ; equatorial periphery roughly 
ovoid, weakly lobate, with two well-developed, much thickened and delicately 
beaded marginal keels enclosing a relatively wide, slightly inclined peripheral band, 
which widens out gradually towards the last chamber ; axial periphery distinctly 
truncate ; chambers on the dorsal side 17, arranged in 3 dextrally coiled whorls ; 
the initial chambers are exceedingly small, almost indistinct, slightly depressed, 
globular, weakly inflated, and increase very slowly in size ; they are followed by 
relatively larger, globular, inflated chambers which increase moderately in size ; the 
last whorl is composed of 5 large, inflated chambers which are subglobular and increase 
slowly in size except for the last which is crescentic, strongly elongated in the direc- 
tion of coiling, and constitutes about \ of the test ; on the ventral side the chambers 
are 5, large, inflated, subglobular, moderately overlapping and increase slowly is size 
except the last one which is ovoid, elongated, strongly inflated and constitutes about 
\ of the test ; sutures on the dorsal side slightly curved, raised and delicately 
beaded, although the inflation of the chambers on both sides makes them appear to 
run in very shallow sutural depressions ; on the ventral side the sutures are curved, 
slightly raised and delicately beaded ; umbilicus irregular in outline, relatively wide, 
shallow, bordered by slightly raised, delicately beaded ridges and covered by complex 
tegilla of which remnants are still preserved ; primary apertures interiomarginal, 
umbilical ; tegilla, with accessory apertures, only poorly preserved ; wall calcareous, 
perforate except for the imperforate keels, peripheral band and tegilla ; surface 
slightly rough, delicately papillose especially on the ventral side with the roughness 
decreasing gradually towards the last chamber. 



in the esna-idfu region, nile valley, egypt 109 

Dimensions of holotype. 

Maximum diameter = 0-43 mm. 

Minimum diameter = 0-32 mm. 

Thickness = 0-22 mm. 

Variation. The main variation observed in specimens of G. fornicata globulo- 
camerata is in the degree of globularity of the last chambers and the degree of surface 
roughness. 

Remarks. All members of the G. fornicata group are generally characterized 
by an early globigerine part, and later crescentic chambers which are strongly 
curved and distinctly elongated in the direction of coiling. The present form, 
however, represents a distinct type of this group in which the early globigerine 
character extends to most of the final whorl, while the last one or two chambers still 
keep the characteristic chamber form which is strongly elongated in the direction 
of coiling. As all the other characters of the G. fornicata group are retained in the 
present form, and as it has a slightly different stratigraphical range from G. fornicata 
fornicata Plummer, it is here considered as a distinct subspecies. The name 
G. fornicata globulocamerata describes the globular character of most of its chambers. 

G. fornicata globulocamerata is believed to have evolved from G . fornicata fornicata 
Plummer, and into G. contusa sensu Troelsen, as suggested by the morphology and 
stratigraphical distribution of these forms. 

Holotype. P. 45532. 

Paratypes. P.45533-34. 

Horizon and locality. Holotype, PL 14, figs. 2a-c, and paratype PI. 13, 
figs, xa-c, from samples No. 4 and 3 respectively, Abou Saboun. 

Stratigraphical range. In the Esna-Idfu region, G. fornicata globulocamerata 
occurs as a common to abundant form throughout the Lower Maestrichtian G. 
fornicata Zone, fading out gradually upwards in the section and dying out completely 
below the overlying G. gansseri Zone. 

Globotruncana fornicata manaurensis Gandolfi 
(PL 13, figs. 2a-c) 

J955 Globotruncana fornicata manaurensis Gandolfi : 41, pi. 2, fig. la-c, text-fig. 9 (la-c ; 

2a-c) . 

Description. Test medium-sized, unequally biconvex, coiled in a low trocho- 
spire ; dorsal side convex, moderately arched and slightly inflated, ventral side 
almost flat, slightly raised and weakly inflated ; equatorial periphery subcircular, 
slightly lobate, with two well-developed, closely spaced, thickened marginal keels ; 
axial periphery subangular, subtruncate ; chambers on the dorsal side are not all 
clear, but appear to be 18 in number, arranged in 3 dextrally coiled whorls ; the 
initial chambers are very small, almost indistinct and are followed by slightly larger, 
globular, inflated chambers which become roughly crescentic towards the last whorl 
and increase moderately in size ; the last whorl is composed of 6 (5 + 1 abortive) 



no UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

large chambers which are highly arched, distinctly elongated in the direction of 
coiling and increase slowly in size ; on the ventral side the chambers are 5, large, 
ovoid, and distinctly overlapping while they increase slowly in size ; each chamber is 
surrounded by a horseshoe-shaped, delicately beaded raised ridge ; sutures on the 
dorsal side strongly curved, distinctly raised, much thickened and limbate ; on the 
ventral side the sutures are strongly curved forward, slightly raised and limbate; 
umbilicus roughly pentagonal in outline, wide, deep, surrounded by much-thickened 
ridges and covered by complex tegilla, of which remnants are still preserved ; 
primary apertures interiomarginal, umbilical ; tegilla, with accessory apertures, only 
poorly preserved ; wall calcareous, perforate except for the imperforate keels, 
peripheral band and tegilla ; surface smooth. 

Dimensions of described specimen. 
Maximum diameter = 0-41 mm. 
Minimum diameter = 0-35 mm. 

Thickness = 0-22 mm. 

Remarks. Gandolfi (1955) considered this subspecies to be the ancestral stock 
from which both the G. fornicata and the G. contusa groups have evolved, through 
G. fornicata fornicata Plummer in the former, and G. contusa scutilla Gandolfi in the 
latter. He also mentioned a somewhat dubious relationship with what he described 
as the G. caliciformis-intermedia group and suggested the evolution of the present 
subspecies from G. lapparenti lapparenti (Brotzen) [= G. linneiana linneiana 
(d'Orbigny)]. 

The present study substantiates Gandolfi's suggestion in part, namely that 
G. fornicata manaurensis evolved from G. linneiana linneiana (d'Orbigny) and that 
it possibly evolved into G. fornicata fornicata Plummer. Transitional stages 
between the present subspecies and G. tricarinata tricarinata (Quereau), were also 
recorded (e.g. PI. 14, figs. ya-c). 

Specimens of G. fornicata manaurensis , although rare in the samples studied, 
compare well with Gandolfi's original description and figures, and with topotype 
material kindly forwarded to the present author by Dr. R. Gandolfi. 

Hypotypes. P45535-36. 

Horizon and locality. Figured specimen from Sample No. 14, G. A 314 
section. 

Stratigraphical range. Globotruncana fornicata manaurensis was described by 
Gandolfi (1955) from the Manaure shale of northeastern Colombia where he considered 
its range as Coniacian-Santonian. In the Esna-Idfu region it occurs as a very rare 
form in the Lower Maestrichtian G. fornicata Zone only. 

Globotruncana fundiconulosa Subbotina 

J 953 Globotruncana fundiconulosa Subbotina : 200, 201, pi. 14, figs, la-^c ; pi. 15, figs. 

\a~ib. 
IQ 55 Globotruncana wiedenmayeri wiedenmayeri Gandolfi : 71, pi. 7, figs. ^a-c. 
? 1955 Globotruncana wiedenmayeri magdalenaensis Gandolfi : 72, pi. 7, figs. j,a-c. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT m 

Remarks. The forms described by Gandolfi (1955) as G. wiedenmayeri wieden- 
mayeri and G. wiedenmayeri magdalenaensis are morphologically similar to the 
present species, and have the same stratigraphical range. They are thus considered 
to be junior synonyms, as previously mentioned by Berggren (1962). 

Hypotype. P. 45537. 

Horizon and locality. Hypotype from sample No. 18, W. El-Sharawna 
section. 

Stratigraphical range. The species was recorded by Subbotina (1953) to range 
through the Campanian-Maestrichtian of the U.S.S.R., and by Gandolfi (1955) from 
the Campanian-Maestrichtian of northeastern Colombia. In the Esna-Idfu region 
G. fundiconulosa occurs as a rare form in the Lower Maestrichtian G. fornicata Zone 
and the lower part of the overlying G. gansseri Zone where it dies out completely. 

Globotruncana gagnebini Tilev 
(PI. 2, figs, ifl-4^ ; PL 3, figs. la-d, ^a-d, 6) 

1951 Globotruncana gagnebini Tilev : 50-56, pi. 3, figs. 2-5, text-figs, iqa-e, i^a-ijd. 

1951 Globotruncana ventricosa White ; Bolli : 190, text-fig. le. 

1951a Globotruncana cretacea Cushman ; Nakkady (pars) : 57-58, pi. 2, fig. 2D, E, non A-C. 

1952 Globotruncana gagnebini Tilev ; Tilev : 50-56, pi. 3, figs. 2-5, text-figs. i^a-e, 150-170". 
1955 Globotruncana ventricosa ventricosa (White); Gandolfi : 22, 23 ; pi. 1, figs. ^a-c. 

*955 Globotruncana area caribica Gandolfi : 64, pi. 5, figs. $a-c. 
1957a Globotruncana gagnebini Tilev ; Bolli : 59, pi. 14, figs. 5a-c. 

Description. (Specimen, PL 2, figs. la-d.) Test large, planoconvex, umbilico- 
convex, coiled in a very low trochospire ; dorsal side almost flat, ventral side distinctly 
protruding ; equatorial periphery roughly ovoid, slightly lobate, with two well- 
developed, thickened, beaded keels enclosing a narrow peripheral band ; axial 
periphery truncate ; chambers on the dorsal side 14, arranged in 3 dextrally coiled 
whorls ; the initial ones are small, inflated, globigerine, and increase slowly in size ; 
the last whorl is composed of 5 J, large, crescentic chambers which are elongated in 
the direction of coiling and increase very rapidly in size ; on the ventral side the 
chambers are 5j, large, raised, distinctly protruding, subglobular in the early part 
and elongate later ; sutures on the dorsal side curved, raised and beaded ; on the 
ventral side they are radial or very slightly curved forward and depressed ; umbilicus 
wide, deep, bordered by raised, thick, limbate ridges and covered by complex tegilla 
of which remnants are still preserved ; primary apertures interiomarginal, umbilical ; 
tegilla with accessory apertures only poorly preserved ; wall calcareous, perforate 
except for the imperforate keels, peripheral band and tegilla ; surface smooth except 
for a few scattered papillae on the early part. 

Dimensions of described specimen. 

Maximum diameter = 0-42 mm. 

Minimum diameter = 0-35 mm. 

Thickness = 0-22 mm. 



2 upper cretaceous-lower tertiary foraminifera 

Main variation. 

i. The test is small to large, subcircular to ovoid, moderately to strongly elongate. 

2. The dorsal side is either flat, very slightly raised or even slightly depressed, 

while the ventral side is always protruding, sometimes strongly so that the 

protruding ventral mass lies almost at right angles to the marginal periphery. 

Equatorial periphery subcircular to ovoid, slightly to moderately lobate ; 

axial periphery moderately to distinctly truncate. 
The two marginal keels are either equally developed or the ventral keel is 

sometimes reduced on the last chamber (e.g. PL 2, fig. 26). 
The keels, sutures and umbilical flange can either be heavily beaded through- 
out or beaded in the early part, thickened and limbate in the later part. 
Chambers on the dorsal side 14-16, arranged in 3 whorls, generally dextrally 

coiled (all studied specimens coiled dextrally). 
Chambers in the last whorl 4-6, most commonly 5, large, moderately or 
strongly elongated in the direction of coiling, increasing very rapidly in size. 
The last chamber is either well-developed and constitutes {— I of the test 
(e.g. PL 2, fig. 1 ; PL 3, fig. 3), or is sometimes reduced in size, becoming 
much smaller than the penultimate (PL 2, fig. 2). 
9. The umbilicus varies in shape, but is always wide, deep, and surrounded by a 
raised umbilical flange which is either heavily beaded or just thickened and 
limbate. 
10. The surface is generally smooth but is sometimes covered by large scattered 
papillae especially on the ventral side. 

Remarks. Globotruncana gagnebini was first described by Tilev (1951) who 
mentioned that it morphologically resembles G. pendens Vogler, G. ventricosa White 
and G. lugeoni Tilev, but is quite distinct. 

Bolli (195 1) and Gandolfi (1955) described as G. ventricosa White, and G. ventricosa 
ventricosa (White) respectively, forms which are actually G. gagnebini Tilev, as in 
part reconsidered by Bolli (1957a). Gandolfi also described as G. area caribica, 
a form which appears to be transitional between G. gagnebini Tilev and G. aegyptiaca 
aegyptiaca Nakkady, and is here considered to be a junior synonym of the former. 
Gandolfi's form closely resembles the specimen here figured, PL 3, figs. la-d. 

Berggren (1962) considered G. gagnebini Tilev to be a junior synonym of G. 
aegyptiaca aegyptiaca Nakkady, but the present study showed clearly that the 
morphological features of the two species strongly warrant their separation in 
spite of their apparent similarity. G. gagnebini is distinguished from G. aegyptiaca 
aegyptiaca by its elongate, tightly coiled, ovoid test ; its greater number of chambers 
in the last whorl which increase very rapidly in size ; its weakly lobate periphery, 
more closely spaced keels and less rough surface. 

Globotruncana gagnebini is believed to have evolved from G. ventricosa White by 
reduction in the size of test and in the number of chambers in the last whorl, by 
more rapid increase in the size of the chambers, and by the development of an 
elongate test as well as a slightly rougher surface. The morphological characters and 
stratigraphical distribution of the two species are strongly in favour of this propo- 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 113 

sition which is substantiated by the occurrence of several transitional stages (see 
PI. 2, figs. ^a-d). 

On the other hand, forms which can be morphologically considered as transitional 
between G. gagnebini and G. aegyptiaca aegyptiaca were recorded, and may suggest 
the evolution of the former into the latter. But the fact that the two species have 
always been confused with each other does not allow one to distinguish precisely 
their respective stratigraphical ranges which are generally considered to be the same. 
However, the apparent morphological similarity of the two species may be due to 
" parallel evolution " from two distinct but genetically related forms. 

Hypotypes. P. 45538. 

Horizon and locality. Figured specimens, P1.2, figs. la-d, 2a-d ; PI. 3, 
fig. 6, from sample No. 16, W. El-Sharawna section ; PL 2, figs, ^a-d, which is a 
transitional stage to G. ventricosa White, and PL 3, figs, ^a-d, from sample No. 18, 
W. El-Sharawna section ; PL 2, figs. <\a-d, from sample No. 4, Abou Saboun section ; 
PL 3, figs. la-d, from sample No. 11, Gebel Owaina section. 

Stratigraphical range. Globotruncana gagnebini was first described by Tilev 
(1951) from the Maestrichtian of southeastern Turkey where it was recorded to 
range throughout the stage. It was also recorded from the Maestrichtian of Trinidad 
(Bolli 1951, 1957a) as ranging throughout the G. gansseri and the Abathomphalus 
mayaroensis Zones. 

In the Esna-Idfu region, G. gagnebini Tilev floods the Maestrichtian part of the 
studied sections ; it is abundant in the G. fornicata Zone, floods the G. gansseri Zone 
and is rare in the G. esnehensis Zone, where it dies out completely. 



Globotruncana cf. gagnebini Tilev 

(PL 3, figs. 2a-d) 

Remarks. The tendency of G. gagnebini Tilev to have a slightly raised dorsal 
side was mentioned by Tilev (1951) and was observed in the present study. How- 
ever, none of Tilev's figures nor the typical specimens here studied, was found to have 
a conical dorsal side. The form here described as G. cf. gagnebini is closely related to 
Tilev's form, but differs only in having a gently coned, dorsal side. Morphologically, 
this form should be considered separately, but because it was found to be rather 
rare in the samples studied, it is provisionally described as G. cf. gagnebini. 

Hypotype. P.45539. 

Horizon and locality. Figured specimens from sample No. 4, Abou Saboun 
section. 

Stratigraphical range. Globotruncana cf. gagnebini is rare in the Lower 
Maestrichtian G. fornicata Zone and in the basal part of the Middle Maestrichtian 
G. gansseri Zone of the Esna-Idfu region. 



ii 4 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Globotruncana gansseri dicarinata Pessagno 

(PI. 5, figs. 4a-d) 

i960 Globotruncana (Rugotruncana) gansseri dicarinata Pessagno : 103, pi. 2, figs. 9-1 1 ; 
pi. 3, figs. 1-3 ; pi. 5, fig. 2. 

Description. Test large, planoconvex, umbilico-convex, coiled in a very low 
trochospire ; dorsal side flat, ventral side strongly protruding, equatorial periphery 
roughly ovoid or rather quadrate, distinctly lobate, with two well-developed, 
thickened, heavily beaded, widely spaced keels, reduced to a single keel on the last 
chamber ; axial periphery truncate in the early part, subangular in the later ; 
chambers on the dorsal side are not all clear because of the surface rugosity, but 
appear to be 16 in number, arranged in 3 dextrally coiled whorls ; the initial chambers 
are extremely small, indistinct, almost masked by the surface rugosity, increase very 
slowly in size and are followed by globular to crescentic, weakly inflated chambers 
which also increase slowly in size ; the last whorl is composed of 5 large, crescentic 
chambers which increase rapidly in size ; on the ventral side the chambers are 5 
large, angular conical and strongly protruding ; sutures on the dorsal side curved, 
raised and heavily beaded ; on the ventral side they are straight, radial and depres- 
sed ; umbilicus roughly pentagonal in outline, wide, deep, surrounded by a raised, 
beaded, umbilical flange in the early part, which fades out gradually towards the last 
chamber, and is covered by complex tegilla of which remnants are still preserved; 
primary apertures interiomarginal, umbilical ; tegilla with accessory apertures only 
poorly preserved ; wall calcareous, perforate except for the imperforate keels, 
peripheral band and tegilla ; surface rough, heavily papillose, nodose, or spinose in 
the early part with the rugosity decreasing gradually towards the last chamber. 

Dimensions of described specimen. 
Maximum diameter = 0-50 mm. 

Minimum diameter = 0-35 mm. 

Thickness = 0-26 mm. 

Remarks. Pessagno (i960) stated that this subspecies differs from G. gansseri 
gansseri Bolli in having a distinct double keel and well-developed rugosities in the 
early stages. He also added that it is intermediate between Rugoglobigerina rugosa 
subrugosa Gandolfi and G. gansseri gansseri Bolli and that it has evolved from the 
former by dorsal flattening and the migration of the double-keel band to the dorsal 
periphery. However, this subspecies appears to be more closely related to G. 
gagnebini Tilev from which it differs only by the well developed surface rugosity. 
Thus its assignment to G. gansseri may seem doubtful, as the last mentioned species 
is characterized by its entirely single keel. However, the fact that Bronnimann & 
Brown (1956) and Pessagno (i960) observed a double-keeled rugoglobigerine 
nepionic stage in thin sections of G. gansseri gansseri, may support Pessango's 
hypothesis that the latter subspecies has evolved from G. gansseri dicarinata by the 
gradual reduction of the ventral keel. The specimen here figured as G. gansseri 
dicarinata Pessagno conforms well with the holotype, while the paratype figured 
by Pessagno (i960) lacks the typically crescentic shape of the chambers on the 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 115 

dorsal side and the distinctly lobate periphery characteristic of the holotype. 
Examination of topotype specimens, kindly presented by Dr. E. A. Pessagno, Jr., 
showed clearly that they are more like the figures of the paratype of Pessagno than 
those of the holotype. The limited number of specimens found in the present study 
does not allow the evolutionary history of this subspecies to be followed although its 
evolution from G. gagnebini Tilev is not excluded, despite Pessagno's statements. 

Hypotype. P. 45540. 

Horizon and locality. Figured specimen, from sample No. 16, Gebel Owaina 
section. 

Stratigraphical range. Globotruncana gansseri dicarinata was first described 
by Pessagno (i960) from the Rio Yauco mudstone formation of Puerto Rico where it 
was stated to be common in the lower part of the Maestrichtian G. tilevi Subzone, 
and to constitute a particular faunal zonule, the G. gansseri dicarinata Zonule. 

In the Esna-Idfu region, it occurs as a rare to common form in the Middle Maes- 
trichtian G. gansseri Zone, and dies out completely in the basal part of the Upper 
Maestrichtian G. esnehensis Zone. 

Globotruncana gansseri gandolfii subsp. nov. 

(PI. 5, figs. 2a-d) 

J 955 Globotruncana gansseri gansseri Bolli ; Gandolfi : 69-70, pi. 6, figs. 8a-c, text-fig. 11b. 

Diagnosis. A Globotruncana with small to large, quadrate, umbilico-convex 
test ; weakly inflated chambers on dorsal side, slightly imbricate in last whorl ; 
radial depressed ventral sutures, thin marginal keel slightly shifted towards dorsal 
side ; rough surface. 

Description. Test large, roughly quadrate in outline, planoconvex, umbilico- 
convex, coiled in a very low trochospire ; dorsal side almost flat and somewhat 
imbricate although the chambers are weakly inflated and slightly overlapping; 
ventral side strongly inflated and distinctly protruding ; equatorial periphery 
roughly quadrate, moderately lobate, with a single, delicately beaded keel which is 
slightly shifted towards the dorsal side ; axial periphery subangular, subtruncate ; 
chambers on the dorsal side about 17 in number, arranged in 2I- dextrally coiled 
whorls ; the initial chambers are exceedingly small, globular, slightly inflated and 
almost masked by the surface rugosity ; they increase very slowly in size and are 
followed by relatively larger, subglobular, slightly inflated chambers which increase 
moderately in size ; the last whorl is composed of 4^, large, roughly ovoid chambers 
which increase moderately in size, although the last chamber is slightly smaller than 
the penultimate ; on the ventral side the chambers are 4^, large, subglobular, 
strongly inflated and distinctly protruding ; sutures on the dorsal side slightly 
curved, almost radial, raised and beaded, although the inflation of the chambers 
makes them appear to be slightly depressed in part, especially towards the inner 
whorl ; on the ventral side the sutures are straight, radial, and strongly incised 



n6 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

umbilicus roughly quadrate in outline, relatively wide, deep, and covered by complex 
tegilla of which remnants are still preserved ; primary apertures interiomarginal, 
umbilical ; tegilla with accessory apertures only poorly preserved ; wall calcareous, 
perforate except for the imperforate keel and tegilla ; surface on the dorsal side 
rough in the early part, covered with numerous small papillae which decrease 
gradually towards the last chamber ; on the ventral side the surface is very rough, 
heavily papillose or even nodose. 

Dimensions of holotype. 

Maximum diamter = 0-48 mm. 

Minimum diameter = 0-33 mm. 

Thickness = 0-28 mm. 

Main variation. 

1. Chambers 13-18, arranged in 2§~3 whorls, generally dextrally coiled. 

2. Chambers in the last whorl 4-5, flat to slightly inflated, slightly to moderately 

imbricate, increasing slowly in size except for the last, which is either 
slightly smaller or slightly larger than the penultimate. 

3. The surface can either be rough throughout, heavily nodose or even spinose, 

or it can be delicately papillose in the early part and smooth later. 

Remarks. Gandolfi (1955) described as G. gansseri gansseri Bolli from the 
Colon shale of northeastern Colombia, a form which differs from the holotype of 
Bolli (1951). Such a form is abundant in the samples studied; its morphological 
characters and stratigraphical range warrant its separation from the central type 
and therefore it is here considered as a new subspecies of G. gansseri Bolli. It is 
named G. gansseri gandolfii, after Dr. R. Gandolfi. It is believed to have evolved from 
either G. gansseri gansseri (Bolli) or G. gansseri dicarinata Pessagno, as suggested by 
the morphological features and stratigraphical ranges of these forms. On the other 
hand, G. gansseri gandolfii is morphologically related to Globotruncana arabica sp. 
nov. which appears slightly higher in the section and thus may possibly represent 
its direct descendant. 

Holotype. P. 45541. 

Paratypes. P. 45542. 

Horizon and locality. Holo- and paratypes, from sample No. 21, W. El- 
Sharawna section, Esna-Idfu region. 

Stratigraphical range. In the Esna-Idfu region G. gansseri gandolfii appears 
as a common to a flood form in the upper part of the Middle Maestrichtian G. gansseri 
Zone, and continues as a rare to a common form in the overlying G. esnehensis Zone 
where it dies out completely immediately below the disconformity separating this 
zone from the overlying basal Tertiary. All records of G. gansseri gansseri Bolli 
from rocks younger than the Middle Maestrichtian (e.g. Gandolfi 1955 and Berggren 
1962) most probably refer to the present subspecies. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 117 

Globotruncana gansseri gansseri Bolli 

(PL 5, figs. la-d; PL n, fig. 3) 

1951 Globotruncana gansseri Bolli : 196, 197 ; pi. 35, figs. 1-3. 

1956 Rugotruncana gansseri (Bolli) Bronnimann & Brown : 549-550 ; pi. 23, figs. 7—9 ; 
text-fig. 23. 
? i960 Globotruncana monmouthensis Olsson : 50-51, pi. 10, figs. 22-24. 
? i960 Globotruncana (Rugotruncata) gansseri, Bolli; Pessagno : 102, pi. 4, fig. 11. 

Emended diagnosis. A Globotruncana with large, planoconvex, umbilico- 
convex test, large chambers increasing very rapidly in size in last whorl ; chambers 
typically crescentic and strongly elongated in direction of coiling on dorsal side, and 
angular conical, distinctly protruding on ventral side ; entirely single keel in last 
whorl, curved, raised, beaded dorsal sutures and slightly curved, depressed ventral 
ones ; very large umbilicus and moderately to heavily papillose surface in early part 
of test. 

Description. Test large, planoconvex, umbilico-convex, coiled in a very low 
trochospire ; dorsal side flat, ventral side strongly inflated and distinctly protruding ; 
equatorial periphery roughly ovoid, moderately lobate, with a single well-developed, 
beaded keel ; axial periphery truncate, angular acute ; chambers on the dorsal side 
15, arranged in 2 J, dextrally coiled whorls ; the initial chambers are small, globular, 
compressed ; they increase slowly in size and are followed by typically crescentic, 
much flattened chambers which increase rapidly in size ; the last whorl is composed 
of 5 large, crescentic, flattened chambers which are elongated in the direction of 
coiling and increase rapidly in size ; on the ventral side the chambers are 5, large, 
angular conical, strongly inflated and distinctly protruding ; sutures on the dorsal 
side curved, raised and beaded ; on the ventral side the sutures are very slightly 
curved to almost straight, radial and depressed ; umbilicus roughly pentagonal in 
outline, very wide, deep, bordered by raised, beaded ridges and covered by complex 
tegilla of which remnants are still preserved ; primary apertures interiomarginal, 
umbilical ; tegilla, with accessory apertures, only poorly preserved ; wall calcareous, 
perforate, except for the imperforate keel and tegilla ; surface smooth on the dorsal 
side, coarsely papillose on the ventral, with the papillae becoming coarse and scattered 
towards the last chamber. 

Dimensions of described specimen. 
Maximum diameter = 0-62 mm. 
Minimum diameter = 0-47 mm. 

Thickness = 0-30 mm. 

Main variation. 

1. Chambers 14-16, arranged in 2J-3 whorls, generally dextrally coiled (all 

studied specimens coiled dextrally). 

2. Chambers in the last whorl 4^-5. 

Remarks. Globotruncana gansseri was first validly described by Bolli (1951) 
although he had previously (1950) used the name without giving any description or 



[18 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

figure. Gandolfi (1955) described G. gansseri subgansseri as a new subspecies thus 
changing the name of Bolli's form to G. gansseri gansseri. However, the form 
figured by Gandolfi (1955) as G. gansseri gansseri Bolli was found to differ from the 
holotype of Bolli and is thus considered here separately. 

Bronnimann & Brown (1956) introduced Rugotruncana as a new genus and 
included G. gansseri Bolli in it. However, as mentioned above, Rugotruncana 
Bronnimann & Brown 1956 is considered a junior synonym of Globotruncana Cush- 
man 1927. These authors (1956) showed by thin sections of G. gansseri gansseri 
that the early part of the test has two well-developed marginal keels in spite of the 
entirely single-keeled last whorl. Pessagno (i960) also observed a double-keeled, 
rugoglobigerine nepionic stage in thin sections of G. gansseri gansseri , but added that 
some individuals may lack this initial double keel. 

Olsson (i960) described as G. monmoathensis , a form which most probably belongs 
to the present subspecies. 

Globotruncana gansseri Bolli (1951) was found to include the following four distinct 
subspecies : 

Globotruncana gansseri gansseri Bolli 1951. 
Globotruncana gansseri subgansseri Gandolfi 1955. 
Globotruncana gansseri dicarinata Pessagno i960. 
Globotruncana gansseri gandolfii subsp. nov. 

However, because of its entirely double keel, G. gansseri dicarinata appears to 
be morphologically distinct, despite the fact that thin sections of G. gansseri gansseri 
showed a double-keeled nepionic stage. Further study may prove that it should 
be treated separately although it has some features in common with the G. gansseri 
group. 

Gandolfi (1955) suggested the evolution of G. gansseri gansseri Bolli from G. 
rosetta pettersi Gandolfi which was said to appear in older strata and to die out 
completely before the first appearance of G. gansseri gansseri. However, Pessagno 
(i960) suggested the evolution of G. gansseri gansseri from G. gansseri dicarinata, 
while the present study favours its evolution from G. rosetta rosetta (Carsey). On 
the other hand, G. gansseri gansseri might possibly have evolved in two directions, 
one leading to G. gansseri subgansseri and the other to G. gansseri gandolfii. 

Hypotype. P.45543. 

Horizon and locality. Figured specimen, from Sample No. 18, W. El-Shar- 
awna section. 

Stratigraphical range. Globotruncana gansseri gansseri was first described 
by Bolli (1951) from the Maestrichtian Lantern marl, Guayaguayare formation of 
Trinidad and all subsequent references restricted its range to the Maestrichtian. 

In the Esna-Idfu region, G. gansseri gansseri appears in the basal part of the 
Pecten (Chlamys) mayereymari marl (Pecten farafraensis marl) ; it floods this rock unit 
and the basal part of the overlying shale member, characterizing a particular faunal 
zone, the G. gansseri Zone. It continues in the Upper Sharawna shale, fading out 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 119 

gradually upwards in the section and dies out completely in the basal part of the 
overlying G. esnehensis Zone. 

Bolli (1957a) recognized the G. gansseri Zone in the Maestrichtian of Trinidad, 
where he considered it to start slightly above the base of the Maestrichtian. How- 
ever, Bronnimann & Brown (1956) considered the range of this species to be Lower 
to Middle Maestrichtian, while the G. gansseri Zone is here considered to represent 
the Middle Maestrichtian only. 

Globotruncana gansseri subgansseri Gandolfi 
(PL 5, figs. 3a-d) 
1955 Globotruncana gansseri subgansseri Gandolfi : 70, pi. 6, figs. ja-c. 

Description. Test small, subcircular in outline, almost planoconvex, umbilico- 
convex, coiled in a low trochospire ; dorsal side flat although the early chambers are 
slightly inflated and weakly raised above the circumambient, last whorl ; ventral side 
strongly inflated and distinctly protruding ; equatorial periphery subcircular, 
moderately lobate, with a single, delicately beaded marginal keel ; axial periphery 
acute ; chambers on the dorsal side 18, arranged in 3 dextrally coiled whorls ; the 
initial ones are very small, globigerine and weakly inflated, they increase slowly in 
size and are followed by slightly larger, globular, inflated chambers which increase 
moderately in size ; the last whorl is composed of 6 relatively large, crescentic 
chambers which increase slowly in size except for the last one which is slightly 
smaller than the penultimate ; on the ventral side the chambers are 6, subglobular, 
strongly inflated, distinctly protruding and increase slowly in size ; sutures on the 
dorsal side curved, slightly raised and delicately beaded ; on the ventral side they 
are radial and strongly depressed ; umbilicus roughly hexagonal in outline, relatively 
large, deep and covered by complex tegilla of which remnants are still preserved ; 
primary apertures interiomarginal-umbilical ; tegilla with accessory apertures only 
poorly preserved ; wall calcareous, perforate, except for the imperforate keel, 
peripheral band and tegilla ; surface rough, especially on the ventral side where it is 
coarsely papillose in the early part, with the roughness decreasing gradually towards 
the last chamber ; the papillae sometimes taper out simulating thick spine-like 
projections especially along the periphery. 

Dimensions of described specimen. 
Maximum diameter = 0-35 mm. 

Minimum diameter = 0-29 mm. 

Thickness = 0-24 mm. (of last chamber) 

Remarks. Globotruncana gansseri subgansseri was first described by Gandolfi 
(1955) who remarked that this subspecies differs from G. gansseri gansseri in having 
a smaller test, a greater number of chambers in the last whorl, more inflated chambers, 
and a less evident keel. 

Globotruncana gansseri subgansseri is believed to have evolved from G. gansseri 



i2o UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

gansseri Bolli, and may possibly represent a transitional stage between the latter and 
G. lugeoni Tilev, although no direct evidence was recorded. 

Hypotype. P.45544. 

Horizon and locality. Figured specimen from sample No. 16, Gebel Owaina 
section. 

Stratigraphical range. Gandolfi (1955) described G. gansseri subgansseri 
from the Colon shale of northeastern Colombia where its range was described as 
fairly rare in the uppermost Siphogenerinoides bramlettei Zone which he considered to 
be of Maestrichtian age. 

In the Esna-Infu region, G. gansseri subgansseri appears as a rare to common form 
in the Middle Maestrichtian G. gansseri Zone. It increases gradually upwards in 
the section to flood the basal part of the overlying G. esnehensis Zone and then dies 
out completely near the middle part of this zone. 



Globotrunana havanensis Voorwijk 

1937 Globotruncana havanensis Voorwijk : 195, pi. 1, figs. 25, 26, 29. 

? 1946 Globorotalia pshadae Keller : 99, pi. 2, figs. 4-6. 

1951 Globotruncana citae Bolli : 197, pi. 35, figs. 4-6. 

? 1953 Globotruncana citae Bolli ; Papp & Kiipper : 38, pi. 1, figs. ^a-c. 

? 1953 Globorotalia pshadae Keller ; Subbotina : 204, pi. 16, figs. ia-6c. 

1954 Globotruncana citae Bolli ; Ayala : 387, pi. 3, figs. la-c. 

1954 Globotruncana havanensis Voorwijk ; Ayala : 396, pi. 6, figs. "za-c. 

1955 Globotruncana citae Bolli : Gandolfi : 51, pi. 3, figs. na-c. 

1956 Globotruncana citae Bolli ; Knipscheer (in Ganss & Knipscheer) : 624, pi. 2, figs. $a-c. 
1956 Rugotruncana havanensis (Voorwijk) Bronnimann & Brown : 552, pi. 22, figs. 4-6, 

pi. 24, fig. 5. 
19566 Marginotruncana citae (Bolli) Hofker : 334, text-fig. 25. 
1956c Marginotruncana citae (Bolli) ; Hofker : 79, text-fig. 72. 
J957 Globotruncana {Globotruncana) citae Bolli ; Edgell : 111, pi. 1, figs. 13-15. 
1960a Globotruncana citae Bolli ; Hofker : 225, text-figs. 2oa-c. 
i960 Globorotalia pshadae Keller ; Vinogradov : 307, pi. 2, figs. I5a-i66. 
1962 Praeglobolruncana (Praeglobotruncana) havanensis (Voorwijk) Berggren : 26-30, pi. 7, 
figs. la-c. 

Remarks. The taxonomic position of this species has been very much confused ; 
it was defined as a Globotruncana by Voorwijk (1937), as a Globorotalia by Keller 
(1946), Subbotina (1953) and Vinogradov (i960), as a Rugotruncana by Bronnimann 
& Brown (1956) and Pessango (i960), as Marginotruncana by Hofker (19566, c) and 
as Praeglobotruncana by Bolli (1957a) and Berggren (1962). However, the few 
specimens recorded in the present study clearly show that the aperture is interio- 
marginal, umbilical, covered by complex tegilla of which remnants are still preserved, 
and thus prove that the species should be assigned to the genus Globotruncana. 

Hypotypes. P.45657-58. 

Horizon and locality. Hypotypes from sample 23, Gebel Owaina section. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 121 

Stratigraphical range. Globotruncana havanensis was first described by 
Voorwijk (1937) from the Upper Cretaceous of Habana, Cuba. It was also recorded 
from the Maestrichtian of the Caucasus (Keller 1946 and Subbotina 1953), the 
Maestrichtian of Trinidad (Bolli 1951, 1957a), of Austria (Papp & Kiipper, 1953), 
of northeastern Colombia (Gandolfi 1955), of Bavaria (Knipscheer 1956), of Texas 
and of Cuba (Bronnimann & Brown 1956), of northwestern Germany and of Holland 
(Hofker 19566, c), of Australia (Edgell 1957), of Romania (Vinogradov i960) and of 
southern Scandinavia (Hofker 1960a and Berggren, 1962). 

In the Esna-Idfu region, G. havanensis occurs as a rare form throughout the Mae- 
strichtian, increasing gradually upwards in the section, and dying out completely 
below the disconformity separating the Maestrichtian from the overlying Danian. 

Globotruncana leupoldi Bolli 
(PI. 1, figs. 4«-c) 

1945 Globotnmcana leupoldi Bolli : 235, pi. 9, fig. 17 ; text-fig. 1, figs. 25, 26. 

Description. Test medium-sized, subcircular in outline, biconvex, coiled in 
a moderately high trochospire ; dorsal side broadly convex, moderately raised, 
ventral side convex and moderately inflated ; equatorial periphery subcircular, 
distinctly lobate, with two well-developed, thickened, delicately beaded and widely 
spaced marginal keels, becoming single on the last chamber only ; axial periphery 
truncate in the early part, angular and distinctly acute in the later part ; chambers 
on the dorsal side 16, arranged in 3 dextrally coiled whorls ; the initial chambers are 
small, inflated, globigerine, increasing moderately in size and followed by typically 
crescentic, petaloid chambers which increase slowly in size as added ; the last whorl 
is composed of 5 large, typically crescentic, petaloid chambers which are elongated 
in the direction of coiling and increase slowly in size ; on the ventral side the chambers 
are 5, large, roughly ovoid and distinctly outlined with horseshoe-shaped, beaded 
ridges and increase slowly in size ; sutures on the dorsal side are curved, raised and 
beaded ; on the ventral side they are strongly curved forward, thickened, raised and 
beaded ; umbilicus pentagonal in outline, wide, deep, bordered by raised, beaded 
ridges and covered by complex tegilla of which remnants are still preserved ; primary 
apertures interiomarginal, umbilical ; tegilla with accessory apertures only poorly 
preserved ; wall calcareous, perforate, except for the imperforate keels, peripheral 
band and tegilla ; surface smooth. 

Dimensions of described specimen. 
Maximum diameter = 0-45 mm. 
Minimum diameter = 0-37 mm. 

Thickness = 0-22 mm. 

Remarks. Bolli (1945) described G. leupoldi from thin sections only and included 
in its synonymy some of the forms previously described by de Lapparant (1918) 
as Rosalina linnei d'Orbigny " type 5 " and Rosalina stuarti, although the latter is a 
completely distinct form. He also considered some of the forms described by Vogler 



[22 IPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

(1941) as Globotruncana linnet stuarti Vogler and G. linnet marginata (Reuss) to belong 
to G. letipoldi. 

Reichel (1950) considered G. leupoldi as a junior synonym of G. area (Cushman) 
while Papp & Kiipper included it in the synonymy of G. fomicata Plummer, and 
Bronnimann & Brown (1956) followed by Berggren (1962) in that of G. rosetta 
(Carsey). However, Globotruncana leupoldi is too remote to be related to either 
G. fomicata or G. rosetta. It is distinguished from typical G. area, from which it is 
thought to have evolved, by its smaller, slightly compressed test, fewer chambers, 
less beaded keels and sutures, sharply acute axial periphery on the last chamber and 
truncate one on the early chambers, its flattened petaloid last chambers on the 
dorsal side, its single keel on the last one or two chambers and its perfectly smooth 
surface. 

The form described by Olsson (i960) as G. leupoldi is probably G. area or is tran- 
sitional to it. 

Hypotype. P.45545. 

Horizon and locality. Figured specimen, from sample No. 18, W. El-Sharaw- 
na section. 

Stratigraphical range. Globotruncana leupoldi was described by Bolli (1945) 
from the Wangschichten limestone of Switzerland where it was found to range 
throughout the Upper Campanian-Maestrichtian. 

In the Esna-Idfu region G. leupoldi ranges throughout the G. fomicata and the 
G. gansseri Zones. It fades out gradually towards the top part of the latter zone 
and dies out completely in the basal part of the overlying G. esnehensis Zone. 

Globotruncana lugeoni Tilev 
(PI. 6, figs. la-d ; PL n, fig. 2) 

1951 Globotruncana lugeoni Tilev : 41-46, pi. 1, figs. 5, 6, text-figs, xoa-c, na-d, ? i2a-e. 
(See also Tilev 1952 where figures are repeated.) 

Description. Test large, planoconvex, coiled in a very low trochospire ; dorsal 
side almost flat and slightly imbricate although the chambers are slightly inflated 
and moderately overlapping ; ventral side strongly inflated and distinctly protruding ; 
equatorial periphery roughly ovoid, elongate, slightly lobate, with a single well- 
developed, heavily beaded marginal keel which is slightly shifted towards the dorsal 
side ; axial periphery subangular ; chambers on the dorsal side about 18, arranged in 
3.I dextrally coiled whorls, increasing very slowly in size ; initial chambers small 
subglobular, weakly inflated and almost masked by the surface rugosity ; they are 
followed by slightly larger subglobular chambers ; the last whorl is composed of 6 
subcircular, weakly inflated chambers ; on the ventral side the chambers are 6, 
subglobular, strongly inflated, distinctly protruding and increase so slowly in size 
that they all appear to be roughly equal except for the last ; sutures on the dorsal side 
slightly curved, depressed in the early part, strongly curved, raised, thickened and 
heavily beaded in the later part, although the slight inflation of the chambers makes 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 123 

them appear slightly depressed towards the inner whorl ; on the ventral side the 
sutures are radial and strongly incised ; umbilicus roughly hexagonal in outline, 
moderately wide, deep and covered by complex tegilla of which remnants are still 
preserved ; primary apertures interiomarginal, umbilical ; tegilla, with accessory 
apertures, only poorly preserved ; wall calcareous, perforate, except for the imperfo- 
rate keel and tegilla ; surface rough, heavily nodose in the early part especially on 
the ventral side, with the roughness decreasing gradually towards the last chamber. 

Dimensions of described specimen. 
Maximum diameter = 0-43 mm. 
Minimum diameter = 0-34 mm. 

Maximum thickness = 0-26 mm. (Thickness of last chamber) 

Main variation. 

1. Chambers 13-18, arranged in 2J-3I whorls, generally dextrally coiled (all 

specimens studied coiled dextrally). 

2. Chambers in the last whorl 4-7. 

Remarks. Bronnimann & Brown (1956) followed by Berggren (1962) considered 
this species to be a junior synonym of G. gansseri gansseri Bolli. However, the 
present study showed clearly that the two forms are morphologically distinct and 
should be treated separately. 

The evolutionary history of G. lugeoni Tilev is not clear, but it might have evolved 
from G. gansseri gansseri, although no direct evidence was recorded. 

Tilev (1951, 1952) also described as G. lugeoni var. angulata, a form which appears 
to be quite distinct from the holotype of G. lugeoni and the studied hypotypes. It 
appears to be more closely related to G. stuarti stuarti (de Lapparent), although it 
lacks the characteristic shape of the chambers of the latter species on the ventral side. 
Forms identical with this variety were recorded in the samples studied, but being very 
rare they are not described for the time being. 

Hypotype. P. 45546. 

Horizon and locality. Figured specimen, from sample No. 15, Gebel Owaina 
section. 

Stratigraphical range. Tilev (1951, 1952) recorded G. lugeoni from the 
Maestrichtian of southeastern Turkey stating that its range is more precisely 
considered as Middle Maestrichtian. In the Esna-Idfu region, G. lugeoni Tilev 
occurs as a rare form in the G. gansseri Zone. It gradually increases upwards in the 
section to flood the upper part of this zone and then fades out gradually in the basal 
part of the overlying G. esnehensis Zone, where it dies out completely. 

Globotruncana mariai Gandolfi 

1941 Rosalinella globigerinoides Marie : 239, pi. 36, figs. 338a-c. 

1941 Rosalinella globigerinoides var. sublaevigata Marie : 240, pi. 36, figs. 339<z-c. 

1955 Globotruncana mariai Gandolfi : 33. 



i2 4 UPPER CRETACEOUS-LOWER TERTIARY FOR AMINI FER A 

Remarks. Marie (1941) described Rosalinella globigerinoides as a new species 
from the Campanian, " Belemnitella mucronata chalk " of the Paris Basin. As 
Rosalinella Marie, is a junior synonym of Globotruncana Cushman 1927, the name of 
the present species was automatically changed to Globotruncana globigerinoides 
(Marie) where it became a junior homonym of Globotruncana globigerinoides Brotzen 
1936, which in its turn is a junior synonym of G. cretacea (d'Orbigny) 1840. 

Gandolfi (1955) changed the name of the present species to Globotruncana mariai 
nom. nov. Apparently he named the species after Dr. P. Marie, who first described 
it, and the spelling should have been mariei. Unfortunately, Banner & Blow (i960) 
proposed the name G. mariei for G. cretacea Cushman 1938, which itself is a junior 
homonym of G. cretacea (d'Orbigny) 1840. 

As neither of the names can be changed according to the rules of zoological 
nomenclature, they are both applied here in spite of the confusion which may result. 

Globotruncana mariai is distinguished by its peculiarly shaped, segmented, imbricate 
double keel and wide peripheral band. Marie (1941) also described as R. globi- 
gerinoides var. sublaevigata, a form which only differs from the central type in having 
the two marginal keels unequally projecting. Such a minor variation was found to 
be unworthy of distinction and thus G. globigerinoides var. sublaevigata is included 
here within the central type. 

Hypotype. P.45547. 

Horizon and locality. Hypotype from sample No. 4, Abou Saboun section. 

Stratigraphical range. This species was originally described from the 

Campanian of the Paris Basin (Marie 1941). It occurs as a rare to common form in 

the Lower Maestrichtian G. fomicata Zone of the studied sections, and dies out 
completely in the top part of this zone. 

Globotruncana mariei Banner & Blow 

193 1 Globotruncana area (Cushman) ; Cushman : 59, pi. 11, figs. 6a-c. 

1931 Globotruncana area (Cushman) ; Plummer, (pars) : 195, pi. 13, figs. 7-8C ; non figs. 

ga-c, na-c. 
1936 Globotruncana area (Cushman) ; Cushman : 419, pi. 1, figs, i^a-c. 
1938 Globotruncana cretacea Cushman ; 67, pi. n, figs. 6a-c. 
J 939 Globotruncana cretacea Cushman ; Cushman : 92, pi. 16, figs. 8a-c. 
1946 Globotruncana cretacea Cushman ; Cushman : 151, pi. 62, figs. ja-c. 
1951 Globotruncana cretacea Cushman ; Tilev (pars) ; 62-67, text-figs. z\a-d, non loa-d. 

(See also Tilev 1952 where figures are repeated.) 
1954 Globotruncana cretacea Cushman ; Nakkady & Osman : 79, pi. 19, figs. loa-c. 
i960 Globotruncana mariei Banner & Blow : 8. 

Remarks. Globotruncana mariei was first described by Cushman (1931) as 
Globotruncana area (Cushman). The same author (1938), realizing the difference 
between this form and G. area, considered it as a distinct species and named it 
G. cretacea Cushman. 

Tilev (1951, 1952) stated that although Cushman (1938) had described his G. 
cretacea as " usually having a single keel ", the holotype, as figured by Cushman 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 125 

was shown to have two closely spaced keels. He also noticed that in the specimens 
he studied from the Maestrichtian of southeastern Turkey, there were forms with 
double and single keels. He also considered G. rosetta rosetta (Carsey) as a junior 
synonym of the present species in spite of its priority. 

Bronnimann & Brown (1956) confirmed Tilev's earlier observation stating that 
" In an examination of the holotype of Git. cretacea Cushman, two keels, very close 
together, were observed in all chambers of the last whorl ". These two authors also 
considered the present species to be intermediate between G. lapparenti Brotzen and 
G. rosetta (Carsey). 

Banner & Blow (i960) proved Globigerina cretacea d'Orbigny, 1840, to be a true 
Globotruncana, and thus changed its name to Globotruncana cretacea (d'Orbigny) 
whereby Globotruncana cretacea Cushman 1938, became a junior homonym, which 
they renamed Globotruncana mariei nom. no v. 

Globotruncana mariei is distinguished by its medium-sized, planoconvex to 
unequally biconvex test, its chambers which increase rapidly in size in the last whorl, 
its very closely spaced keels, and strongly overlapping chambers on the ventral side, 
and by its smooth test and somewhat rougher keels. 

Contrary to Tilev's observation (1951, 1952), G. marei is quite distinct from G. 
rosetta rosetta (Carsey), although Bronnimann & Brown (1956) stated that it seems to 
be an incipient form of G. rosetta. 

Nakkady (1951a) described as G. cretacea Cushman from Duwi, Mellaha, Durba 
and Danilli sections, Egypt, forms which include G. stuarti stuartiformis Dalbiez, 
G. aegyptiaca aegyptiaca Nakkady and G. gagnebini Tilev, as examination of his 
specimens (B.M. N.H., P. 41782) has revealed. 

Nakkady also figured as G. pseudocretacea n.sp., a form which most probably 
belongs to G. gagnebini Tilev, or is transitional between it and G. ventricosa White, 
as examination of his type specimens (B.M.N.H., P. 41783-84) has revealed. How- 
ever, Berggren (1962) wrongly considered G. pseudocretacea to be a nomen nudum 
and stated that Nakkady 's specimens were related to G. rosetta rosetta (Carsey). 

Hypotype. P.45548. 

Horizon and locality. Hypotype from sample No. 18, W. El-Sharawna 
section. 

Stratigraphical range. Globotruncana mariei was first described from the 
Upper Campanian, Selma chalk of Tennessee. Most records show that it ranges 
throughout the Upper Campanian and the Maestrichtian. 

In the Esna-Idfu region, G. mariei occurs as a common form throughout the 
Maestrichtian, G. fornicata, G. gansseri and G. esnehensis Zones, being most common 
at the base and fading out gradually upwards in the section. 

Globotruncana orientalis sp. nov. 
(PL 12, figs. t\a-d) 

Diagnosis. A Globotruncana with broadly arched dorsal side and almost flat 
ventral one, two closely spaced keels in early part, reduced to one in the last chambers ; 



i2b UPPER CRETACEOUS-LOWER TERTIARY FOR AMINIFER A 

curved, raised, beaded sutures, wide umbilicus and horseshoe-shaped ridge of beads 
bordering each chamber on ventral side. 

Description. Test large, almost circular in outline, coiled in a relatively high 
trochospire ; dorsal side broadly convex, ventral side flat although the chambers are 
very slightly inflated ; equatorial periphery almost circular, slightly lobate ; axial 
periphery angular, acute, with two heavily beaded keels on the early chambers of the 
last whorl, reduced to a single, well-developed, distinctly beaded keel in the last 
chambers ; chambers on the dorsal side 18 (17 -+- 1 broken), arranged in 3 dextrally 
coiled whorls and slowly and regularly increasing in size ; the initial chambers are 
small, inflated and globigerine, while later chambers are typically crescentic, slightly 
flattened and elongated in the direction of coiling, the last whorl is composed of 6 
large, typically crescentic chambers ; on the ventral side the chambers are 6, ovoid, 
very weakly inflated, slightly overlapping, distinctly outlined with heavily beaded 
horseshoe-shaped rims, and increase so slowly in size that they all appear to be roughly 
equal ; sutures on both sides curved, raised, thickened and heavily beaded ; umbili- 
cus roughly hexagonal in outline, wide, deep, surrounded by slightly raised, heavily 
beaded ridges, and covered by complex tegilla of which remnants are still preserved ; 
primary apertures interiomarginal, umbilical ; tegilla with accessory apertures only 
poorly preserved ; wall calcareous, perforate, except for the imperforate keels, 
peripheral band and tegilla ; surface generally smooth. 

Dimensions of holotype. 

Maximum diameter = 0-50 mm. 

Minimum diameter = 0-45 mm. 

Thickness = 0-25 mm. 

Main variation. 

1. Chambers on the dorsal side 18-21, arranged in 3-3^ whorls, generally dextrally 

coiled. 

2. The last whorl is composed of 5-7 chambers which are large, crescentic and 

increase slowly in size. 

3. In some specimens the ventral keel is completely reduced and the test becomes 

entirely single keeled at least throughout the last whorl. 

Remarks. Globotruncana orientalis is morphologically similar to G. leupoldi 
Bolli, G. conica White, G. esnehensis Nakkady & Osman and to G. sharawnaensis 
sp. nov. However, it is distinguished from G. leupoldi by its flat ventral side, much 
narrower peripheral band and less lobate equatorial periphery. It differs from G. 
conica White by its less conical dorsal side, its early double keel and the horseshoe- 
shaped ridges on the ventral side. Globotruncana esnehensis is entirely single keeled 
and has strongly depressed ventral sutures, while G. sharawnaensis sp. nov. is single 
keeled in the early part becoming double keeled later, has depressed ventral sutures 
and a rougher surface. 

The forms desribed by Cita (1948) and Pessagno (1962) as G. conica White most 
probably belong to tne present species. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 127 

Globotruncana orientalis sp. nov. has possibly evolved from G. area (Cushman) by 
the flattening of the ventral side and the reduction of the ventral keels on the last 
chambers. This is substantiated by the fact that such tendencies were clearly 
observed in specimens of G. area (Cushman). On the other hand, G. orientalis has 
probably evolved into G. esnehensis Nakkady & Osman, although no direct evidence 
was recorded. 

Holotype. P. 45549. 

Paratypes. P. 45550. 

Horizon and locality. Holo- and paratypes from sample No. 18, W. El-Sharaw- 
na section. 

Stratigraphical range. Globotruncana orientalis sp.nov. appears as a common 
to abundant form in the Lower Maestrichtian G. fornicata Zone of the sections 
studied. It continues as an abundant form in the overlying G. gansseri Zone, 
fading out gradually towards its top, and dies out completely in the basal part of the 
G. esnehensis Zone. 



Globotruncana rosetta pettersi Gandolfi 

I 955 Globotruncana rosetta pettersi Gandolfi : 68, pi. 6, figs, ^a-^c, text-fig. 11a. 

1961 Globotruncana cf. rosetta pettersi Gandolfi ; Corminboeuf : 113-114, pi. 1, figs. $a-c. 

Remarks. Globotruncana rosetta pettersi was first described by Gandolfi (1955) as 
a new subspecies from the lower Colon shale of northeastern Colombia where he 
considered its range as Campanian. He stated that the form is entirely single 
keeled, but examination of topotype specimens kindly sent by him to the present 
author, showed forms with 2 keels on the early part of the last whorl, becoming 
single keeled on the later chambers, and others with an entirely single keeled last 
whorl. The entirely single keeled form is similar to the G. gansseri group, especially 
to G. gansseri gandolfii subsp. nov. from which it is only distinguished by its smooth 
surface. Gandolfi also stated that G. rosetta pettersi was found to disappear when the 
first G. gansseri gansseri starts, but in the present study G. rosetta pettersi occurs as a 
common form in the lower part of the G. gansseri Zone. It was neither recorded in 
the underlying G. fornicata Zone nor in the upper part of the G. gansseri Zone. This 
clearly indicates that the range of this subspecies is only Middle Maestrichtian, while 
Gandolfi considered it as Campanian. However, as previously mentioned, the 
Colon shale, which Gandolfi considers as Campanian-Maestrichtian, most probably 
belongs to the Maestrichtian alone, as suggested by its planktonic foraminiferal 
content. This is substantiated by the fact that the present subspecies was also 
recorded from the Maestrichtian of Switzerland as G. cf. rosetta pettersi Gandolfi by 
Corminboeuf (1961). 

Hypotype. P. 45551. 

Horizon and locality. Hypotype from sample No. 23 W. El-Sharawna section. 



128 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

Globotruncana rosetta rosetta (Carsey) 
(PL 8, figs. 3a-d) 

1926 Globigerina rosetta Carsey : 44, pi. 5, figs. $a-c. 

1931 Globotruncana area (non Cushman) ; Plummer (pars) : 195, pi. 13, figs, ga-c, na-c 
(non figs, ja-c, 8a-c). 
? 1937a Globotruncana rosetta (Carsey) Glaessner : 39, pi. 1, figs, \-za-c. 
? 195 1 Globotruncana rosetta (Carsey) : Bandy : 509, pi. 75, figs. ^a—c. 
? 1951 Globotruncana cretacea Cushman ; Tilev (pars) 62-67, text-figs. ioa-d, non 2ia-d 

(see also Tilev 1952 where figures are repeated). 
? 1954 Globotruncana rosetta (Carsey) ; Nakkady & Osman : 84, pi. 19, figs. -ja-c. 
? 1955 Globotruncana rosetta rosetta (Carsey) ; Gandolfi : 66-67, pi- 6, figs. la-c, text-figs. loa-c. 
? 1955 Globotruncana bollii Gandolfi : 62-63, pi. 5, figs. la-c. 

1956 Globotruncana rosetta (Carsey) : Bronnimann & Brown : 545-546, pi. 21, figs. 11-13. 

1962 Globotruncana rosetta (Carsey) : Barr : 575, pi. 70, figs. ^a-c. 

Description. Test large, planoconvex, coiled in a very low trochospire ; dorsal 
side almost flat, ventral side distinctly protruding ; equatorial periphery subcircular, 
moderately lobate, with two very closely spaced keels on the early part of the last 
whorl reduced to a single keel on the later chambers ; axial periphery angular with 
the ventral side almost at right angles to the flat periphery ; chambers on the dorsal 
side 18, arranged in 3 dextrally coiled whorls ; the initial chambers are small, inflated, 
globigerine, increasing slowly in size, and followed by typically crescentic, flattened 
chambers which increase moderately in size ; the last whorl is composed of 6, 
relatively large, typically crescentic, flattened chambers which increase slowly in 
size ; on the ventral side the chambers are 6, relatively large, angular conical, 
strongly inflated, slightly overlapping, distinctly protruding and increase so slowly 
that they appear to be all roughly equal in size ; sutures on the dorsal side curved, 
slightly raised and delicately beaded with the beading fading out gradually towards 
the last chamber ; on the ventral side the sutures are radial and slightly depressed ; 
umbilicus roughly stellate in outline, relatively wide, deep, bordered by delicately 
beaded ridges and covered by complex tegilla of which remnants are preserved ; 
primary apertures interiomarginal, umbilical ; tegilla, with accessory apertures, only 
poorly preserved ; wall calcareous, perforate, except for the imperforate keels, 
peripheral band and tegilla ; surface delicately papillose especially on the ventral 
side and in the early part becoming smoother towards the last chamber. 

Dimensions of described specimen. 
Maximum diameter = 0-52 mm. 
Minimum diameter = 0-47 mm. 

Maximum thickness = 0-30 mm. 

Variation. The main variation observed is in the degree of flattening of the 
dorsal side, protrusion of the ventral side, and surface rugosity. 

Remarks. Globotruncana rosetta rosetta was first described by Carsey (1926) as 
Globigerina rosetta n.sp. White (1928) transferred this species to the genus Globo- 
truncana although his figured specimen probably belongs to the G. stuarti group. 
Plummer (1931) considered the present species to belong to G. area (Cushman) 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 129 

suggesting that the two keeled specimens are juvenile forms while the single keeled 
ones are mature. Since then G. rosetta rosetta has been quite often confused with 
G. area Cushman. G. marginata (Reuss), G. stuarti (de Lapparent) and G. cretacea 
Cushman (= G. mariei Banner & Blow i960). 

Tilev (1951, 1952) included G. rosetta rosetta (Carsey) in the synonymy of G. 
cretacea Cushman 1938 ( = G. mariei Banner & Blow i960) although the former has 
priority. Bronnimann & Brown (1956) partially substantiating Tilev's observation, 
stated that " Examination of the holotype of Globotruncana rosetta (Carsey), in the 
Carsey collection at the University of Texas, reveals that it possesses two keels in 
the early chambers of the last whorl which are very close together. In the ante- 
and penultimate chambers the two keels join ". These two authors also added 
" In an examination of the holotype of Git. cretacea Cushman, two keels, very close 
together, were observed in all chambers of the last whorl. It is intermediate 
between Git. lapparenti Brotzen and Git. rosetta (Carsey) . It seems to be an incipient 
form of Git. rosetta, for all transitions exist between forms corresponding to the holo- 
types of Git. rosetta and Git. cretacea. We suggest that the forms which exhibit two 
keels, close together in all chambers of the last whorl be referred to Git. cretacea 
Cushman, and that the forms which exhibit two keels close together in the early 
chambers of the last whorl and only one keel in the final one or two chambers be 
referred to Git. rosetta (Carsey) ". They also included G. leupoldi Bolli in the 
synonymy of G. rosetta (Carsey). However, the present study has clearly shown 
that G. rosetta rosetta (Carsey), G. cretacea Cushman (= G. mariei Banner & Blow) 
and G. leupoldi Bolli are separate and distinct forms. 

Gandolfi (1955) described as new subspecies of G. rosetta (Carsey), two distinct 
forms which he named Globotruncana rosetta insignis Gandolfi and Globotruncana 
rosetta pettersi Gandolfi, thus changing the name of the present form to Globotruncana 
rosetta rosetta (Carsey) . He did not state whether his G. rosetta rosetta had a double 
keel on the early part or not, and his G. rosetta insignis appears to be synonymous with 
G. fareedi sp. nov., as mentioned earlier (p. 101). Gandolfi also described as G. 
bollii n. sp., a form which may possibly be a junior synonym of G. rosetta rosetta 
(Carsey). Moreover, he suggested that G. rosetta rosetta evolved from G. thalmanni 
thalmanni through G. bollii into G. rosetta pettersi and G. rosetta insignis, while 
Berggren (1962) suggested that G. rosetta evolved from G. mariei. However, the 
evolutionary development of G. rosetta rosetta is not yet clearly understood. It may 
have evolved from G. concavata (Brotzen) or from G. ventricosa White as suggested 
by the morphological features and stratigraphical ranges of these species, but no 
direct evidence was recorded. On the other hand, G. rosetta rosetta probably evolved 
into G. gansseri gansseri (Bolli) as well as giving rise to G. rosetta pettersi. 

Hypotype. P.45552. 

Horizon and locality. Figured specimen from sample No. 16, W. El-Sharaw- 
na section. 

Stratigraphical range. Carsey (1926) described the holotype of G. rosetta 
from the upper Taylor marl (Upper Campanian of Texas), but apparently she had 



130 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFER A 

confused this form with various other species and thus confused its range which she 
stated to be Cenomanian-Maestrichtian. However, all reliable records show that 
the present subspecies ranges throughout the Upper Campanian-Middle Maestrich- 
tian only. In the Esna-Idfu region, G. rosetta rosetta (Carsey) occurs as an abundant 
form in the Lower Maestrichtian G. fornicata Zone, decreasing gradually upwards in 
the section and becoming common or rare in the lower part of the overlying G. 
gansseri Zone, where it dies out completely. 

Globotruncana sharawnaensis sp. nov. 
(PI. 12, figs. ^a-d) 

Diagnosis. A Globotruncana with large, spiroconvex test, single keel in early part 
becoming double in last chamber, depressed ventral sutures and delicately papillose 
surface on ventral side. 

Description. Test large, coiled in a high trochospire ; dorsal side broadly 
convex and highly arched, ventral side almost flat, very slightly raised and weakly 
inflated ; equatorial periphery subcircular, slightly lobate, with a single, well- 
developed, beaded keel on the early chambers of the last whorl and two distinct, 
closely spaced, beaded keels on the last chamber ; axial periphery angular in the 
early part, truncate on the last chamber, where the two marginal keels are very close 
and enclose a very narrow peripheral band ; chambers on the dorsal side 21, arranged 
in 3 dextrally coiled whorls and increase slowly in size ; the initial chambers are small, 
inflated, globigerine, and are followed by roughly quadrangular to crescentic cham- 
bers ; the last whorl is composed of 6\, large chambers, which are generally crescentic 
to quadrilateral ; on the ventral side the chambers are 6|, roughly ovoid to somewhat 
quadrangular, weakly inflated, slightly overlapping, and increase slowly in size; 
sutures on the dorsal side are curved, raised and beaded in the early part and short, 
very slightly curved to almost straight, raised and beaded in the later ; on the ventral 
side the sutures are almost straight, radial and depressed in the early part, slightly 
curved forward and depressed later ; umbilicus polygonal in outline, wide, deep, 
surrounded by slightly raised, delicately beaded ridges and covered by complex, 
tegilla of which remnants are still preserved ; primary apertures interiomarginal, 
umbilical ; tegilla with accessory apertures only poorly preserved ; wall calcareous 
perforate except for the imperforate keels, peripheral band and tegilla ; surface 
smooth on the dorsal side, papillose on the ventral, with the papillae fading out 
gradually on the last two chambers. 

Dimensions of holotype. 

Maximum diameter = 0-50 mm. 

Minimum diameter = 0-40 mm. 

Thickness = 0-28 mm. 

Main variation. 

1. Chambers 18-22, arranged in 3-3 1 whorls, generally dextrally coiled. 

2. The last whorl is composed of 6-7 chambers. 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 131 

3. In some specimens the partly developed secondary keel is completely reduced 
leading to forms with a single keel throughout the last whorl. 

Remarks. Globotruncana sharawnaensis is unique among the known Globotrun- 
cana species, inasmuch as it shows a single keel on the early part of the last whorl and 
a double keel on the last one or two chambers. The tendency to reduce the ventral 
keel in double-keeled globotruncanas was clearly observed in various species which 
normally show a double keel in the early part of the test and become single keeled 
later (i.e. reduction by palingenesis). However, no species has yet been recorded as 
having a single keel in the early stage and a double keel later, although reduction of 
the ventral keel by proterogenesis would produce such forms. 

Forms of G. sharawnaensis, with an entirely single keel appear to be somewhat 
similar to G. conica White. However, G. sharawnaensis is distinguished from 
G. conica by its slightly smaller test, less conical dorsal side and slightly more 
protruding ventral one, its somewhat rough ventral side, partially developed 
ventral keel and acute axial periphery. It differs from G. orientalis sp. nov. in its 
depressed ventral sutures, the character of its keels and the slightly rougher surface 
on the ventral side. Globotruncana esnehensis Nakkady & Osman is distinguished 
from G. sharawnaensis sp. nov. by its dome-shaped test, less protuding and more 
undulating ventral side, more inflated chambers on the dorsal side, wider umbilicus, 
smoother surface, and entirely single keel. 

Very little is known about the evolutionary history of G. sharawnaensis sp. nov. 
However, it may have evolved from G. area (Cushman) into G. conica White and/or 
G. esnehensis Nakkady & Osman, although no direct evidence was recorded. 

Holotype. P45553. 

Paratypes. P. 45554. 

Horizon and locality. Holo- and paratypes, from sample No. 20, W. 
El-Sharawna section. 

Stratigraphical range. Globotruncana sharawnaensis sp. nov. is common in 
the Middle Maestrichtian G. gansseri Zone of the studied sections, and dies out com- 
pletely in the basal part of the overlying G. esnehensis Zone. 

Globotruncana stuarti parva Gandolfi 
(PL 9, figs, za-d) 

1951 Globotruncana stuarti (de Lapparent) ; Bolli : 196, pi. 34, figs. 10-12. 

1951 Globotruncana stuarti (de Lapparent) ; Tilev (pars) ; 34-41, text-figs. 8a-d non ja-d, 

non ga-d. (See also Tilev 1952 where figures are repeated.) 
J955 Globotruncana stuarti parva Gandolfi : 65, pi. 5, figs. ja-c. 
1956 Globotruncana aegyptiaca Nakkady ; Said & Kenawy : 150, pi. 5, figs, iga-c. 

Description. Test small, subcircular, unequally biconvex, dorsal side very 
slightly raised or nearly flat with a slightly raised part in the centre from which the 
surface gently slopes radially towards the periphery ; ventral side strongly pro- 



132 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFER A 

truding ; periphery subcircular in outline, nearly continuous, transversely acute, 
with a single well-developed beaded keel ; chambers on the dorsal side 20, arranged 
in 4 dextrally-coiled whorls ; the initial chambers are very small, slightly inflated, 
globigerine, and are followed by nearly crescentic chambers which increase very 
slowly in size till near the beginning of the last whorl where they enlarge very rapidly ; 
the last whorl is composed of 4, large, angular conical chambers which are narrow and 
strongly elongated in the direction of coiling ; the first one is typically crescentic on 
the dorsal side, while the last 3 are roughly trapezoidal ; on the ventral side the 
chambers are 4^, typically quadrangular with blunt corners and roughly parallel 
curved sides ; they are strongly overlapping, distinctly outlined, and strongly 
inflated especially around the umbilicus, with the surface somewhat steeply sloping 
towards the thinned-out periphery ; sutures on the dorsal side very slightly curved 
or nearly straight, angular, limbate, raised and heavily beaded ; on the ventral side 
they are strongly curved forward, limbate, raised and heavily beaded ; umbilicus, 
narrow, roughly pentagonal in outline, relatively deep, surrounded by thickened, 
raised, beaded ridges, and covered by complex tegilla of which remnants are still 
preserved ; primary apertures interiomarginal, umbilical, tegilla with accessory 
apertures only poorly preserved ; wall calcareous, perforate, except for the imperfo- 
rate keel and tegilla ; surface smooth and finely porous. 

Dimensions of described specimen. 
Maximum diameter = 0-46 mm. 
Minimum diameter = 0-36 mm. 

Thickness = 0-26 mm. 

Main variation. 

1. Chambers on the dorsal side 15-20 arranged in 3-4 whorls, usually dextrally 

coiled (of 75 specimens picked at random, 2 coiled sinistrally) . 

2. Chambers in the last whorl 4-5, the first one or two usually crescentic, the last 

three trapezoidal and much bigger. 

3. The surface is generally smooth but in some specimens small scattered papillae 

cover the surface of the initial chambers. 

Remarks. Globotrnncana stuarti parva Gandolfi has always been confused with 
G. stuarti stuarti (de Lapparent), from which it is believed to have evolved. How- 
ever, it can be clearly distinguished by its much smaller size, fewer chambers in the 
last whorl, its nearly straight sutures on the dorsal side, its strongly protruding 
umbilical side, and by the fact that the last whorl is always much larger than the rest 
of the test. 

Hypotype. P. 45555- 

Horizon and locality. Figured specimen from sample No. 23, W. El- 
Sharawna section. 

Stratigraphical range. Globotruncana stuarti parva Gandolfi is recorded 
from the lower part of the G. gansseri Zone of the studied sections, where it is found 



IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 133 

in great abundance in association with G. stuarti stuarti, G. stuarti stuartiformis and 
G. stuarti subspinosa. A few meters higher in the succession, all the other subspecies 
disappear, but G. stuarti parva continues as a common to rare form in the overlying 
G. esnehensis Zone. 

Gandolfi (1955) described G. stuarti parva from the Colon shale of northeastern 
Colombia, and considered its range as Campanian-Maestrichtian. However, the 
distribution of Globotruncana species in the Colon shale seems to indicate that the 
whole formation is Maestrichtian in age as not a single exclusively Upper Campanian 
species is present even in the lowest part. 

G. stuarti parva was also recorded from the Maestrichtian rocks of Trinidad 
(Bolli 1951) and of southeastern Turkey (Tilev 1951, 1952) where it was lumped 
with G. stuarti stuarti. 

Globotruncana stuarti stuarti (de Lapparent) 

(PL 8, figs. 4a-d ; PL 9, figs. la-d) 

19186 Rosalina stuarti de Lapparent : 11-14, pi. 1, figs. 5, 6, 7, text-figs. 4, 5. 

1928 Globotruncana rosetta (Carsey) ; White : 286, pi. 39, figs. ia-e. 

1941 Globotruncana stuarti (de Lapparent) Vogler : 289, pi. 23, figs. 40-43. 

1941 Globotruncana linnei stuarti Vogler (pars) : 289, pi. 24, fig. 8, non figs. 9-13. 

1945 Globotruncana stuarti (de Lapparent) ; Bolli : 236, pi. 9, fig. 18, text-fig. 1 (27, 28). 

1948 Globotruncana stuarti (de Lapparent) ; Cita : 160-161, pi. 4, figs. ja-c. 

1949 Globotruncana {Globotruncana) stuarti (de Lapparent) ; Reichel : 613-615, pi. 16, 
fig. 10, pi. 17, fig. 10, text-fig. ja. 

1951a Globotruncana area (Cushman) ; Nakkady (pars) : 56-57, pi. 1, fig. 4A, non B-E. 
1 95 1 Globotruncana (Globotruncana) stuarti (de Lapparent) ; Noth : 78, pi. 8, figs, \ia-c. 
? 195 1 Globotruncana (Globotruncana) rosetta (Carsey) ; Noth : 78, pi. 8, figs. i$a-c. 

1951 Globotruncana stuarti (de Lapparent); Tilev (pars) : 34-41, pi. 1, fig. 3, text-figs. ~ja-d, 
non figs. 8a-d, ga-d (see also Tilev 1952 where figures are repeated). 

1952 Globotruncana stuarti (de Lapparent) ; Sigal : 40, text-fig. 42. 

1Q 55 Globotruncana (Globotruncana) stuarti (de Lapparent) ; Dalbiez : 163-164, Chart 2, 

text-figs. \a-c. 
*955 Globotruncana stuarti stuarti (de Lapparent), Gandolfi : 64-65, pi. 5, figs. 6a-c. 
1956 Globotruncana stuarti (de Lapparent) ; Knipscheer : 52, pi. 4, figs. iga-20c, text-figs. 

2, 3- 

1962 Globotruncana (Globotruncana) stuarti stuarti (de Lapparent) ; Pessagno : pi. 2, figs. 1-3. 

Emended diagnosis. A Globotruncana with large, circular, biconvex test ; 
strongly protruding ventral side, and slightly conical dorsal one ; non-lobate entire 
periphery, axially strongly acute ; thinned-out, continuous, entirely single keel ; 
large number of chambers (18-28) increasing constantly and regularly in size 
and strongly elongated in direction of coiling ; large number of whorls (3-4) and 
large number of chambers in last whorl (6-7) ; shape of last chambers on dorsal side 
roughly trapezoidal ; strongly overlapping quadrangular chambers on ventral side ; 
short, slightly curved, raised beaded sutures on both sides. 

Description. (Specimen, PL 8, figs <\a-d.) Test large, very nearly circular, 
lenticular, nearly equally biconvex ; dorsal side slightly raised, very broadly and 
gently conical ; ventral side convex, moderately protruding ; equatorial periphery 



i 3 4 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 

circular, non-lobate, almost entire, with a single, well-developed, beaded keel which 
slightly weakens on the last chambers ; axial periphery strongly acute ; chambers on 
the dorsal side 21 arranged in 3! dextrally coiled whorls ; the initial chambers are 
small, inflated, globigerine and are followed by crescentic chambers which increase 
slowly and regularly in size as added ; the last whorl is composed of 6, narrow 
chambers which increase slowly in size, and are strongly elongated in the direction 
of coiling ; the first two are nearly crescentic, the last four roughly trapezoidal ; on the 
ventral side the chambers are 6, typically quadrangular with blunt corners and 
roughly parallel curved sides ; they are strongly overlapping, distinctly outlined and 
strongly inflated with the sides gently sloping towards the marginal keel ; sutures on 
the dorsal side short, slightly curved, raised and delicately beaded ; on the ventral 
side the sutures are slightly raised and beaded, slightly curved, tending to be nearly 
straight, except when they curve strongly around the umbilicus to form the umbilical 
flange ; umbilicus medium sized, hexagonal in outline, relatively deep, surrounded by 
thickened, raised, beaded ridges, and covered by complex tegilla of which remnants 
are still preserved ; primary apertures interiomarginal, umbilical ; tegilla with acces- 
sory apertures only poorly preserved ; wall calcareous, perforate, except for the 
imperforate keel and tegilla ; surface smooth, with a few small papillae scattered on 
the ventral side. 

Dimensions of described specimen. 
Maximum diameter = 0-53 mm. 
Minimum diameter = 0-48 mm. 

Thickness = 0-26 mm. 

Main variation. 

1. The dorsal side is very slightly raised to moderately conical, while the ventral 

side is always moderately to strongly protruding. 

2. Chambers, 18-28, arranged in 3^-4 whorls, generally dextrally coiled. 

3. Chambers in the last who